Devices and methods for delivery of valve prostheses

ABSTRACT

A valve prosthesis and implantation device, and methods for use are provided. The devices may be used for transcatheter delivery of an aortic valve prosthesis or transapical delivery of a mitral valve prosthesis. The implantation device utilizes movable claspers for both positioning and anchoring the valve prosthesis, reducing the extent of imaging needed during the implantation procedure.

PRIORITY CLAIM

This application is a continuation of Ser. No. 12/748,059, filed Mar.26, 2010, now U.S. Pat. No. 8,540,767, which claims the benefit of U.S.Provisional Application Nos. 61/211,430, filed Mar. 30, 2009,61/211,431, filed Mar. 30, 2009; 61/211,432, filed Mar. 30, 2009;61/211,433, filed Mar. 30, 2009; and 61/228,423, filed Jul. 24, 2009,all of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The subject matter described herein relates to medical devices andmethods for the implantation of a sutureless prosthetic heart valveusing minimally invasive procedures.

BACKGROUND

Prosthetic heart valves are used to replace damaged or diseased heartvalves. In vertebrate animals, the heart is a muscular organ with fourpumping chambers: the left and right atria and the left and rightventricles, each provided with its own one-way valve. The natural heartvalves are identified as the aortic, mitral (or bicuspid), tricuspid andpulmonary valves. Prosthetic heart valves can be used to replace any ofthese naturally occurring valves, although repair or replacement of theaortic or mitral valves is more common since they reside in the leftside of the heart where pressures are the greatest.

A conventional heart valve replacement surgery involves accessing theheart in the patient's thoracic cavity through a longitudinal incisionin the chest. For example, a median sternotomy requires cutting throughthe sternum and forcing the two opposing halves of the rib cage to bespread apart, allowing access to the thoracic cavity and heart within.The patient is then placed on cardiopulmonary bypass which involvesstopping the heart to permit access to the internal chambers. Such openheart surgery is particularly invasive and involves a lengthy anddifficult recovery period.

Minimally invasive surgical techniques are evolving, where a valveprosthesis can be introduced into a patient using a catheter that isintroduced via a small incision that provides access to, for example, afemoral artery or the heart. A major issue during heart valvereplacement is positioning the prosthetic valve within a small,approximately 2-5 mm, range at the target site. Medical doctors havetried a variety of methods to confirm their judgment during heart valvereplacement procedures, including various marking systems, contrast dyeinjections multiple times along the procedure, and viewing angleadjustments in the imaging systems. However, there are limitations withthese methods and the current imaging systems. For example, the standarderror of the current imaging systems is about 2 mm, and operatorhandling introduces additional variability. Furthermore, heart movementby itself can shift the target landing site by 2-5 mm. All these make itvery difficult to land a prosthetic valve accurately.

Another critical issue with sutureless valves is valve migration. Forexample, when an aortic prosthetic valve is deployed, 100-200 mmHgpressure loads on the aortic valve immediately. The pressure times thevalve surface area produces a substantial load force on the prostheticvalve and can cause valve migration towards the aortic arch. The othercause of valve migration is tilted valve landing. When tilted, theprosthetic valve will have a larger surface area facing the blood flow,which could push the prosthetic valve into the aorta.

There remains a need in the art for improved valve prosthesis anddelivery devices for introducing a valve prosthesis into a patient.

The foregoing examples of the related art and limitations relatedtherewith are intended to be illustrative and not exclusive. Otherlimitations of the related art will become apparent to those of skill inthe art upon a reading of the specification and a study of the drawings.

BRIEF SUMMARY

The following aspects and embodiments thereof described and illustratedbelow are meant to be exemplary and illustrative, not limiting in scope.

In one aspect, a valve prosthesis is described. The valve prosthesis, inone embodiment, is comprised of a support frame radially expandablebetween a compact condition and an expanded condition, the support framehaving an outer surface and defining a central orifice about an axisalong an inflow-outflow direction. In one embodiment, the valveprosthesis is a sutureless cardiac valve prosthesis.

In one embodiment, the support frame comprises a plurality of flexiblelinks arranged wherein one portion of the support frame can expandindependently of the remaining portion.

The valve prosthesis also comprises a plurality of flexible leafletsattached to the support frame to provide a one-way valve in the orificewhen the support frame is in its expanded condition and at least onevalve clasper movable along the axis between a nesting position with theouter surface of the support frame and an engagement position. In oneembodiment, the at least one valve clasper is physically separated fromthe support frame.

In one embodiment, the at least one valve clasper is comprised of firstand second leg members and a u-shaped member. Each of the first andsecond leg members has a first and second end.

In one embodiment, each of the first ends of the leg members is attachedto the u-shaped member by an apex.

In one embodiment, the second end of each leg member is proximal to thefirst end of each leg member.

In one embodiment, the apex is curved. In one embodiment, the first andsecond leg members are joined to the u-shaped member by the apex,wherein the first and second leg members are approximately parallel toeach other.

In one embodiment, the valve clasper is comprised of a shape-memorymaterial.

In one embodiment, each of the free ends of the leg members terminatesin a detent. In another embodiment, the length of the detent can bevariable. In another embodiment, the detent is comprised of ashape-memory material.

In one embodiment, the support frame has a length L, and the first andsecond leg members are at least L in length. In another embodiment, thesupport frame has a length L, and the first and second leg members areless than L in length. In yet another embodiment, the support frame hasa length L, and the first and second leg members are approximately L inlength.

In another embodiment, the support frame in its expanded condition has aradius r, and the at least one valve clasper is dimensioned toconcentrically nest with the support frame when the support frame is inits expanded condition.

In another embodiment, the at least one valve clasper comprises two,three, four, or five valve claspers.

In an alternative embodiment, the valve claspers are each comprised of au-shaped member. In one embodiment, the u-shaped member has a curvedportion at the distal end of the valve clasper and two straight portionsproximal to the curved portion. The two straight portions on oppositesides of the curved portion each end in a free end.

In one embodiment, the support frame has a length L, and each of thestraight portions of the u-shaped member is at least L in length. Inanother embodiment, the support frame has a length L, and each of thestraight portions of the u-shaped member is less than L in length. Inyet another embodiment, the support frame has a length L and each of thestraight portions of the u-shaped member is approximately L in length.

In one embodiment, each of the free ends of the u-shaped memberterminates in a detent. In another embodiment, the length of the detentcan be variable.

In still another embodiment, the support frame is at least partiallycovered by a covering. In certain embodiments, the covering is a fabric.

In yet another embodiment, the support frame is comprised of ashape-memory material.

In one embodiment, the valve clasper is comprised of a shape-memorymaterial.

In one embodiment, the detent is comprised of a shape-memory material.

In one embodiment, the plurality of flexible leaflets is comprised of abiological material. In certain embodiments, the biological material isporcine or bovine.

In one embodiment, at least a portion of the at least one valve clasperis positioned between the support frame and the covering.

In one embodiment, the support frame comprises at least one fastenermember attached to the support frame to create an orifice between thefastener member and the support frame. In another embodiment, a portionof the at least one valve clasper is positioned in the orifice betweenthe at least one fastener and the support frame.

In one embodiment, when the support frame is in a compact condition, theat least one valve clasper is movable along the axis along aninflow-outflow direction. In another embodiment, when the support frameis in an expanded condition, the at least one valve clasper isrestricted in movement along the axis along an inflow-outflow direction.

In another embodiment, when the support frame is in an expandedcondition, the at least one valve clasper cannot freely move along theaxis along an inflow-outflow direction.

In one embodiment, the valve prosthesis is an aortic valve prosthesis, apulmonary valve prosthesis, or a mitral valve prosthesis.

In another aspect, an implantation device comprised of a valveprosthesis as described above and a delivery device is provided. Thedelivery device, in one embodiment, is comprised of a control unit, anat least one track wire consisting of a proximal end attached to thecontrol unit and a distal end for contact with the at least one valveclasper, and a first sheath for encasing at least a portion of thesupport frame of the valve prosthesis in its compact condition. Thevalve prosthesis comprises at least one valve clasper, wherein the atleast one valve clasper comprises two leg members, two apex members anda u-shaped member. In this embodiment, each of the two leg members has afirst and a second end, wherein the first end of each leg member isattached to the u-shaped member and the second end of each leg member isfree. In another embodiment, the first end of each leg member isattached to the u-shaped member by an apex. In one embodiment, each ofthe apex members is curved and the second ends of each of the leg memberare distal to the first ends of each of the leg members.

In one embodiment, the implantation device further comprises a valveprosthesis pusher wire having a proximal end fixed to the control unitand a distal end for contact with the valve prosthesis.

In another embodiment, the control unit is comprised of a pusher wirecontroller. In still another embodiment, the valve prosthesis pusherwire terminates in a member for engaging the valve prosthesis. In yetanother embodiment, the member for engaging the valve prosthesis pusherwire contacts the proximal end of the valve prosthesis.

In one embodiment, the valve prosthesis engaging member is v-shaped oru-shaped.

In yet another embodiment, the at least one track wire is a hollow trackwire, and a locking wire is disposed within the hollow track wire. Inone embodiment, the locking wire at its distal end has a locking memberto releasably secure the at least one valve clasper to the at least onetrack wire.

In another embodiment, the control unit is comprised of a track wirecontroller.

The implantation device, in yet another embodiment, comprises a secondsheath for encasing the at least one valve clasper.

In one embodiment, the second sheath is positioned serially with anddistal to the first sheath.

In one embodiment, the control unit further comprises a first sheathcontroller.

In another embodiment, the second sheath is movable by means of a secondsheath controller disposed in the control unit, the second sheathcontroller comprised of a second sheath control cable that extends fromthe second sheath to the second sheath controller. In one embodiment,the second sheath controller is located at or near the proximal end ofthe delivery device.

In still another embodiment, the second sheath control cable is hollow.

In another embodiment, the proximal end of the at least one track wireis attached to a release switch in the track wire controller.

In yet another embodiment, the control unit further comprises a firstsheath controller.

In still another embodiment, the control unit is configured forindependent control of each of the at least one track wire and the valveprosthesis pusher wire. In another embodiment, the control unit isconfigured for independent control of each of the at least one trackwire and the second sheath control cable.

In one embodiment, the length of the first sheath is at least the lengthof the distance from an access port to the heart, wherein the distanceis measured through an arterial or venous path.

In one embodiment, the first sheath is straight or curved.

In one embodiment, the second sheath is straight or curved.

In another aspect, an implantation device comprised of a valveprosthesis, wherein the valve prosthesis comprises at least one valveclasper, wherein the at least one valve clasper comprises a u-shapedmember is provided.

In this embodiment, each of the free ends of the u-shaped member islocated proximal to the curved portion of the u-shaped member.

The delivery device, in one embodiment, is comprised of a control unit,an at least one track wire consisting of a proximal end attached to thecontrol unit and a distal end for contact with a free end of the atleast one valve clasper, a first sheath for encasing at least a portionof the at least one valve clasper, and a second sheath for encasing atleast a portion of the valve prosthesis support frame in its compactcondition. The second sheath is positioned serially and distally to thefirst sheath.

In one embodiment, the second sheath encases the support frame of thevalve prosthesis and at least a portion of the at least one valveclasper. In another embodiment, the second sheath encases the supportframe of the valve prosthesis and at least a portion of the curvedregion of the at least one valve clasper.

In yet another embodiment, the at least one track wire is a hollow trackwire, and a locking wire is disposed within the hollow track wire. Inone embodiment, the locking wire at its proximal end has a lockingmember to releasably secure the at least one valve clasper to the atleast one track wire.

In another embodiment, the control unit is comprised of a track wirecontroller.

In another embodiment, the second sheath is movable by means of a secondsheath controller disposed in the control unit, the second sheathcontroller comprised of a second sheath control cable that extends fromthe second sheath to the second sheath controller. In one embodiment,the second sheath controller is located at or near the proximal end ofthe delivery device.

In still another embodiment, the second sheath control cable is hollow.

In another embodiment, the proximal end of the at least one track wireis attached to a release switch in the track wire controller.

In yet another embodiment, the control unit further comprises a firstsheath controller.

In one embodiment, the implantation device further comprises a valveprosthesis pusher wire having a proximal end fixed to the control unitand a distal end for contact with the valve prosthesis.

In another embodiment, the control unit is comprised of a pusher wirecontroller. In still another embodiment, the valve prosthesis pusherwire terminates in a member for engaging the valve prosthesis. In yetanother embodiment, the member for engaging the valve prosthesis pusherwire contacts the proximal end of the valve prosthesis.

In one embodiment, the valve prosthesis engaging member is v-shaped oru-shaped.

In still another embodiment, the control unit is configured forindependent control of each of the at least one track wire and thesecond sheath control cable.

In one embodiment, a clasper multiplex unit is provided. In anotherembodiment, the clasper multiplex unit comprises two or more u-shapedmembers and two or more apex members, wherein a first u-shaped member ispermanently attached to a second u-shaped member via a first and secondapex member and one clasper multiplex leg member. In yet anotherembodiment, the clasper multiplex unit comprises three u-shaped members,six apex members, and three clasper multiplex leg members. In anotherembodiment, the clasper multiplex unit comprises four u-shaped members,eight apex members, and four clasper multiplex leg members.

In still another embodiment, each of the one or more multiplex legmembers comprise a hole approximately at its proximal end.

In one embodiment, one or more multiplex leg members comprises one ormore barbs. In another embodiment, each of the one or more barbs ispresent on opposite sides of the one or more multiplex leg members. Inyet another embodiment, each of a plurality of barbs is present seriallyon one side of the one or more multiplex leg members. In still anotherembodiment, each of the plurality of barbs is present on alternate sidesof at least one multiplex leg member.

In one embodiment, a clasper multiplex unit is provided, wherein theclasper multiplex unit comprises two or more u-shaped members and two ormore apex members, wherein a first u-shaped member is permanentlyattached to a second u-shaped member via a first and second apex member,and wherein the clasper multiplex unit does not comprise a multiplex legmember permanently fixed to the clasper multiplex unit. In anotherembodiment the two or more apex members each comprise a hole. In oneembodiment, the clasper multiplex unit comprises three u-shaped membersand six apex members. In another embodiment, the clasper multiplex unitcomprises four u-shaped members and eight apex members.

In one embodiment, a mechanism for the reversible attachment of aclasper multiplex unit to the control unit of a valve implantationdevice is provided. In this embodiment, the valve implantation devicecomprises a hollow track wire, a lock and release element, a flexibletension element, and a clasper multiplex unit. In another embodiment,the flexible tension element comprises a distal loop end. In anotherembodiment, the lock and release element is encased at least partiallywithin the hollow track wire and is attached at its proximal end to thecontrol unit of the implantation device. In yet another embodiment, theflexible tension element is encased at least partially within the hollowtrack wire and is attached at its proximal end to the control unit ofthe implantation device. In one embodiment, the distal end of theflexible tension element extends distal to the distal end of the lockand release element.

In one embodiment, the flexible tension element is comprised of amonofilament, multifilament or braided multifilament structure. Inanother embodiment, the flexible tension element is a wire, thread ormonofilament. In another embodiment the flexible tension element iscomprised of catgut, silk or linen. In yet another embodiment, theflexible tension element is nylon or polypropylene. In yet anotherembodiment, the flexible tension element is comprised of a shape memorymetal.

In one embodiment, a method for reversibly attaching a clasper multiplexunit to a control unit of a valve implantation device is provided. Inanother embodiment, the method comprises 1) threading a distal loop endof a flexible tension element through the hole of a clasper multiplexunit leg member; 2) moving a lock and release element distal through thedistal loop end of the flexible tension element; and 3) moving a hollowtrack wire in a distal direction until the hollow track wire encases atleast the distal loop end of the flexible tension element and a portionof the clasper multiple unit leg member.

In one embodiment, a method for releasing a clasper multiplex unit froma control unit of a valve implantation device is provided. In anotherembodiment, the method comprises, 1) moving a hollow track wire in aproximal direction to uncover the proximal end of a clasper multiple legmember; 2) moving a lock and release element in a proximal directionuntil the lock and release element is not positioned through a distalloop end of a flexible tension element; and 3) moving the hollow trackwire, the lock and release element and the flexible tension element in aproximal direction until the flexible tension element is not positionedthrough a hole of the clasper multiplex unit leg member.

In one embodiment, a mechanism for reversibly attaching a valveimplantation device to a clasper multiplex unit is provided. In thisembodiment, the mechanism comprises a valve implantation device, whereinthe implantation device comprises a lock and release element, a flexibletension element and a hollow track wire, a clasper multiplex unit, and aflexible leg member. In one embodiment, the flexible leg member isreversibly attached at its proximal end to a distal loop end of aflexible tension element, and the flexible leg member is reversibly orpermanently attached at its distal end to a clasper multiplex unit or toa valve prosthesis support frame. In one embodiment, the proximal end ofthe flexible tension element is attached to a control unit of a valveimplantation device. In one embodiment, the clasper multiplex unitcomprises a plurality of multiplex unit leg members. In anotherembodiment, the clasper multiplex unit does not comprise a multiplexunit leg member.

In one embodiment, a method for reversibly attaching a clasper multiplexunit from a control unit of a valve implantation device is provided. Inthis embodiment, the method comprises, 1) interlocking the proximal endof a flexible leg to a distal loop end of a flexible tension element;and 2) moving a hollow track wire in a distal direction until the hollowtrack wire encases at least the proximal portion of the flexible leg.

In one embodiment, a method for releasing a clasper multiplex unit froma control unit of a valve implantation device is provided. In thisembodiment, the method comprises, 1) moving a hollow track wire in aproximal direction so that the hollow track wire does not encase theproximal end of a flexible leg member; and 2) pulling the hollow trackwire and a flexible tension element in a proximal direction, wherein theflexible leg member straightens such that the flexible leg member is nolong interlocked with the flexible tension element.

In another aspect, a method for deploying a cardiac valve prosthesis isprovided. The method comprises providing an implantation device asdescribed above, wherein the valve prosthesis comprises at least onevalve clasper, wherein the at least one valve clasper comprises au-shaped member and two leg members; inserting the implantation deviceinto a heart chamber of a patient; guiding the implantation device to aposition such that the second sheath encasing the at least one valveclasper passes through and extends beyond a cardiac valve in the heartof the patient; manipulating the implantation device to expose the atleast one valve clasper and to anchor the at least one valve clasper ina sinus of the cardiac valve; adjusting by means of the control unit theposition of the valve prosthesis such that a distal edge of the valveprosthesis is disposed approximately adjacent to the at least one valveclasper; sliding the first sheath in a proximal direction to release thevalve prosthesis from the first sheath, whereby the valve prosthesisexpands to its expanded condition to sandwich tissue of the cardiacvalve between the valve prosthesis support frame and the at least onevalve clasper; and removing the delivery device and the introducer fromthe patient.

In one embodiment, sliding the first sheath in a proximal directioncomprises pulling the first sheath controller in a proximal directionwhile the valve prosthesis is held stationary.

In one embodiment, the implantation device is inserted through anintroducer which has been inserted in a heart left ventricle of thepatient.

In yet another embodiment, the step of providing an implantation devicecomprises providing a implantation device wherein the at least one valveclasper is encased in a second sheath on said delivery device. Inanother embodiment, guiding the implantation device comprises guidingthe implantation device to position the second sheath through and beyondthe cardiac valve in the patient. In yet another embodiment, the secondsheath is positioned in the left atrium of the heart.

In one embodiment, manipulating the implantation device to expose the atleast one valve clasper comprises manipulating the implantation deviceto move the second sheath to expose the at least one clasper. In anotherembodiment, manipulating the implantation device to move the secondsheath to expose the at least one clasper comprises pulling a secondsheath controller in a proximal direction while the at least one valveclasper is held stationary.

In one embodiment, an imaging system is used to position the first andsecond sheaths of the delivery device prior to uncovering the at leastone valve clasper.

In one embodiment, the method comprises deploying a valve prosthesis,wherein the valve prosthesis is an aortic valve prosthesis. In anotherembodiment, the method comprises inserting the delivery device throughthe patient's thoracoabdominal region and into the left ventricle at ornear the apex.

In one embodiment, the method further comprises advancing the secondsheath through the aortic annulus into the left atrium and positioningthe first sheath near the aortic annulus; advancing the second sheath ina distal direction to uncover the at least one valve clasper, whereinthe at least one valve clasper expands radially within the left atrium;pulling back on the second sheath controller until the u-shaped memberof the at least one valve clasper contacts the aortic sinus; advancingthe first sheath until the distal end of the first sheath isapproximately adjacent to the proximal end of the second sheath or untilthe distal end of the first sheath contacts the aortic annulus; pullingback on the first sheath while the valve prosthesis remains stationaryto uncover and deploy the valve prosthesis; moving the at least onetrack wire release switch in a proximal direction while holding thelocking wire stationary to release the leg members of the at least onevalve clasper from the at least one track wire; moving the pusher wirecontroller in a proximal direction to disengage the at least one pusherwire engager from the valve prosthesis; advancing the first sheath in adistal direction until the distal end of the first sheath abuts theproximal end of the second sheath; and pulling back on the deliverydevice to remove the delivery device from the patient.

In one embodiment, the method comprises deploying a valve prosthesis,wherein the valve prosthesis is a pulmonary valve prosthesis. In anotherembodiment, the method comprises inserting the delivery device throughthe patient's femoral vein and advancing the delivery device through theinferior vena cava and into the right atrium.

In one embodiment, the method further comprises advancing the secondsheath through the tricuspid annulus into the right ventricle, advancingthe second sheath through the pulmonary annulus and positioning thesecond sheath in the pulmonary artery; advancing the second sheath in adistal direction to uncover the at least one valve clasper, wherein theat least one valve clasper expands radially within the pulmonary artery;pulling back on the second sheath controller until the u-shaped memberof the at least one valve clasper contacts the pulmonary sinus;advancing the first sheath until the distal end of the first sheath isapproximately adjacent to the proximal end of the second sheath or untilthe distal end of the first sheath contacts the aortic annulus; pullingback on the first sheath while the valve prosthesis remains stationaryto uncover and deploy the valve prosthesis; moving the at least onetrack wire release switch in a proximal direction while holding thelocking wire stationary to release the leg members of the at least onevalve clasper from the at least one track wire; moving the pusher wirecontroller in a proximal direction to disengage the at least one pusherwire engager from the valve prosthesis; advancing the first sheath in adistal direction until the distal end of the first sheath abuts theproximal end of the second sheath; and pulling back on the implantationdevice to remove the implantation device from the patient.

In one embodiment, the method comprises deploying a valve prosthesis,wherein the valve prosthesis is a mitral valve prosthesis. In anotherembodiment, the method comprises inserting the implantation devicethrough the patient's femoral vein and advancing the implantation devicethrough the inferior vena cava and into the right atrium.

In one embodiment, the method further comprises advancing the distal endof the implantation device through the tricuspid annulus into the rightventricle, performing a transeptal puncture; advancing the distal end ofthe implantation device through the left atrium and through the mitralannulus, positioning the second sheath in the left ventricle andpositioning the first sheath in the left atrium; advancing the secondsheath in a distal direction to uncover the at least one valve clasper,wherein the at least one valve clasper expands radially within the leftventricle; pulling back on the second sheath controller until theu-shaped member of the at least one valve clasper contacts the mitralsinus; advancing the first sheath until the distal end of the firstsheath is approximately adjacent to the proximal end of the secondsheath or until the distal end of the first sheath contacts the mitralannulus; pulling back on the first sheath while the valve prosthesisremains stationary to uncover and deploy the valve prosthesis; movingthe at least one track wire release switch in a proximal direction whileholding the locking wire stationary to release the leg members of the atleast one valve clasper from the at least one track wire; moving thepusher wire controller in a proximal direction to disengage the at leastone pusher wire engager from the valve prosthesis; advancing the firstsheath in a distal direction until the distal end of the first sheathabuts the proximal end of the second sheath; and pulling back on theimplantation device to remove the implantation device from the patient.

In yet another aspect, a device for delivery of a medical prosthesisinto a patient is provided. The device comprises a tubular steering wireextending from a distal end of the device to a proximal end of thedevice, a control unit at the proximal end of the device, a first sheathcomprising an open lumen, the first sheath disposed distally withrespect to the control unit, at least one track wire having a proximalend attached to the control unit and a distal end for contact andcontrol of a medical prosthesis, and a pusher wire having a proximal endfixed to said control unit and a distal end for controlled contact withthe medical prosthesis.

In one embodiment, the control unit is comprised of a pusher wirecontroller and a track wire controller, wherein the pusher wirecontroller and the track wire controller are independently controllable.

In another embodiment, the proximal end of said at least one track wireis attached to a release switch in the track wire controller.

In yet another embodiment, the proximal end of the at least one pusherwire is attached to a movable control in the pusher wire controller.

In another aspect, a method for deploying a cardiac valve prosthesis isprovided. The method comprises providing an implantation device asdescribed above; inserting the implantation device into a heart chamberof a patient; guiding the implantation device to a position such thatthe second sheath encasing the valve prosthesis is positionedapproximately within the native valve; manipulating the implantationdevice to expose the curved portion of the u-shaped member of the atleast one valve clasper, expose the straight portions of the u-shapedmember and at least a distal portion of the at least one track wire toallow the at least one valve clasper to expand radially into anengagement position; anchoring the at least one valve clasper in a sinusof the cardiac valve; sliding the second sheath in a distal direction torelease at least a portion of the valve prosthesis support frame fromthe second sheath; and sliding the second sheath in a distal directionto release the entire valve prosthesis support frame from the secondsheath, whereby the valve prosthesis expands to its expanded conditionto sandwich tissue of the native cardiac valve between the valveprosthesis support frame and the at least one valve clasper; andremoving the delivery device and the introducer from the patient.

In this embodiment, leaflets of the native cardiac valve are curvedtoward the distal end of the implantation device which has entered theheart chamber.

In one embodiment, manipulating the implantation device to expose thecurved portion of the u-shaped member of the at least one valve claspercomprises moving the second sheath in a distal direction. In anotherembodiment, exposing the straight portion of the at least one valveclasper and at least a distal portion of the at least one track wirecomprises moving the track wire control unit in a distal direction whileholding the first sheath stationary.

In one embodiment, sliding the second sheath in a distal directioncomprises pushing the second sheath controller cable in a distaldirection while holding the implantation device stationary.

In one embodiment, inserting the implantation device into a heartchamber comprises inserting the implantation device into the femoralartery and advancing the implantation device through the aortic archinto the left atrium. In this embodiment, the cardiac valve prosthesisis a aortic valve prosthesis.

In one embodiment, inserting the implantation device into a heartchamber comprises inserting the implantation device through anintroducer which has been inserted in a heart left ventricle of thepatient and advancing the implantation device to the left ventricle. Inthis embodiment, the cardiac valve prosthesis is a mitral valveprosthesis.

In yet another aspect, an implantation device is provided whichcomprises a flexible framework comprising a plurality of prostheticleaflets; a plurality of valve claspers movably attached to the flexibleframework wherein the valve clasper comprises a clasper ear and twoclasper shafts; a first sheath which encases the flexible framework in acompact state and which comprises a clasper pusher; a second sheathwhich encases the plurality of claspers in a compact state; a clasppusher located in the second sheath and a valve stopper located in saidfirst sheath; wherein the first sheath is located distal to the secondsheath prior to deployment of the flexible framework in the annulus.

In still another aspect, a method for deploying a cardiac valveprosthesis is provided. The method comprises providing a cardiacimplantation device as described above, inserting the implantationdevice into the femoral artery and guiding the implantation devicethrough the femoral artery to the left ventricle of the heart until thefirst sheath is located within the annulus of the left ventricle and thesecond sheath is located in the left atrium; sliding the second sheathin a proximal direction to uncover the plurality of valve claspers suchthat the clasper ears extend radially within the left atrium; pushingthe valve claspers distally until the clasper ears contact the floor ofthe aortic valve sinus; sliding the first sheath distally to uncover theflexible framework such that the flexible framework extends radially toform an expanded flexible framework and each native heart valve issandwiched between the clasper ear and the expanded flexible framework.

In addition to the exemplary aspects and embodiments described above,further aspects and embodiments will become apparent by reference to thedrawings and by study of the following descriptions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of one embodiment of a valve prosthesissupport frame with a plurality of claspers.

FIG. 1B is a perspective view of one embodiment of a valve prosthesissupport frame with a plurality of valve claspers.

FIG. 1C is a perspective view of one embodiment of a valve prosthesissupport frame.

FIG. 1D is a perspective view of one embodiment of a valve prosthesissupport frame in a partially expanded condition.

FIG. 1E is a top view of one embodiment of a valve prosthesis supportframe with a plurality of valve claspers.

FIGS. 2A and 2B illustrate a perspective view of a plurality of valveclaspers with detents.

FIG. 3A illustrates a valve prosthesis support frame in a flat form witha plurality of valve claspers and a covering.

FIG. 3B illustrates a valve prosthesis support frame in a flat form witha plurality of valve claspers, engagement fasteners and a covering.

FIGS. 4A-4D illustrate a top view of a valve prosthesis support framewith movably connected claspers in which the support frame is in acompact (FIGS. 4A and 4C) or an expanded (FIGS. 4B and 4D) condition.

FIGS. 4E and 4F illustrate a top view of a valve prosthesis supportframe with engagement fasteners in a compact (FIG. 4E) or expanded (FIG.4F) condition.

FIG. 5A is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure in its compact condition insitu, wherein an apex member connects a leg member and a u-shapedmember. The valve clasper is in an engagement position.

FIG. 5B is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure in its compact condition insitu, wherein an apex member connects a leg member and a u-shapedmember. The valve clasper is in a nested position.

FIG. 5C is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure in the expanded condition insitu, wherein an apex member connects a leg member and a u-shapedmember.

FIG. 5D is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure having engagement fasteners andin its compact condition in situ. The valve clasper is in an engagementposition.

FIG. 5E is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure having engagement fasteners andin its compact condition in situ. The valve clasper is in a nestedposition.

FIG. 5F is a transverse view of a valve clasper movably connected to aprosthetic valve support frame structure having engagement fasteners andin the expanded condition in situ.

FIG. 5G is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itscompact condition in situ. The valve clasper is in an engagementposition.

FIG. 5H is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itsexpanded condition in situ. The valve clasper is in a nested position.

FIG. 5I is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itscompact condition in situ.

FIG. 5J is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itscompact condition in situ. The valve clasper is in an engagementposition.

FIG. 5K is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itsexpanded condition in situ. The valve clasper is in a nested position.

FIG. 5L is a transverse view of one embodiment of a valve claspermovably connected to a prosthetic valve support frame structure in itscompact condition in situ.

FIG. 6A illustrates a valve prosthesis support frame in a flat form witha plurality of valve claspers fixed to the support frame, a plurality ofprosthetic leaflet suture lines and a covering.

FIG. 6B illustrates the top view of a valve prosthesis support framewith a plurality of valve claspers in which the plurality of valveclaspers are fixed to the support frame and the valve prosthesis supportframe is in its compact condition.

FIG. 6C shows the top view of a valve prosthesis support frame with aplurality of valve claspers in which the plurality of valve claspers arefixed to the support frame and the valve prosthesis support frame is inits expanded condition.

FIG. 7A showed a valve prosthesis with a sheath in situ wherein thesupport frame is in a compact condition and the valve claspers are in anested position.

FIG. 7B illustrates a prosthetic valve with movably connected claspersdeployed in a native cardiac valve.

FIGS. 8A-8H are schematic illustrations of one embodiment of animplantation device and a method for implanting a valve prosthesis in anative valve of a heart.

FIG. 9A-9Q provides more detailed views of one embodiment of animplantation device including cross-sectional views showing theplacement of the various implantation device components within theimplantation device.

FIGS. 10A-10C illustrate various embodiments for connecting track wiresto valve claspers.

FIGS. 11A-11B illustrate one embodiment of a valve prosthesisimplantation device with control unit, wherein the valve prosthesis isboth in a compact condition (FIG. 11A) and an expanded condition (FIG.11B).

FIG. 11C illustrates one embodiment of an implantation device controlunit.

FIG. 12A illustrates one embodiment of a valve prosthesis implantationdevice.

FIGS. 12B-12D provide cross-sectional views of one embodiment of a valveprosthesis implantation device.

FIGS. 13A-13D provide detailed view of one embodiment of an implantationdevice.

FIGS. 14A-14D illustrate manipulation steps for one embodiment of animplantation device.

FIGS. 15A-15C illustrate manipulation steps for one embodiment of animplantation device.

FIGS. 16A-16C illustrate an alternative embodiment for a valveprosthesis support frame.

FIGS. 17A-17B illustrate alternative embodiments for clasper multiplexunits.

FIGS. 17C-17G illustrate alternative embodiments for the leg members ofclasper multiplex units.

FIGS. 17H-17M illustrate alternative embodiments for attachment andrelease clasper multiplex unit leg members.

FIGS. 18A-18B illustrate alternative embodiments for a clasper multiplexunit.

FIG. 18C illustrates an alternative embodiment for a clasper multiplexunit leg member.

FIGS. 19A-19E illustrate an alternative embodiment for reversibleattachment of a valve implantation device to a leg member of a claspermultiplex unit.

FIGS. 20A-20C illustrate an alternative embodiment for release of avalve delivery device from a leg member of a clasper multiplex unit.

FIGS. 21A-21C illustrate an alternative embodiment for reversibleattachment of a valve delivery device to a leg member of a claspermultiplex unit.

FIGS. 22A-22D illustrate an alternative embodiment for release of avalve delivery device from a leg member of a clasper multiplex unit.

FIG. 23 illustrates an introducer inserted in the thoracoabdominalregion.

FIGS. 24A-24H are schematic illustrations of a transapical procedure foraortic valve replacement.

FIGS. 25A-25I are schematic illustrations of an alternative embodimentfor an implantation device and a method for implanting a mitral valveprosthesis in a native mitral valve of a heart.

FIG. 26 illustrates a path for delivery of a prosthetic heart valvewhich includes advancing an implantation device through the inferiorvena cava.

FIG. 27 illustrates a path for delivery of a prosthetic heart valvewhich includes introducing an implantation device into the jugular veinand advancing the device through the superior vena cava.

FIG. 28 illustrates a path for delivery of a prosthetic pulmonary valvewhich includes an implantation device into the jugular vein andadvancing the device through the superior vena cava.

FIGS. 29A-29H illustrates a method of using one embodiment of animplantation device for implanting a prosthetic aortic valve whichincludes advancing the implantation device through the femoral arteryand aortic arch.

FIGS. 30A-30C illustrate an alternative embodiment for a method ofdelivering and deploying a valve prosthesis.

FIGS. 31A-31D illustrates a method for deploying and disconnecting froma prosthetic valve.

DETAILED DESCRIPTION

The present disclosure provides devices, systems and methods for valvereplacement, preferably using a minimally invasive surgical technique.While the devices and methods will have application in a number ofdifferent vessels in various parts of the body, they are particularlywell-suited for replacement of a malfunctioning cardiac valve, and inparticular an aortic valve, a pulmonary valve or a mitral valve. Thedevices and methods are particularly advantageous in their ability toprovide a more flexible prosthetic heart valve implantation device,ensure accurate and precise placement of the prosthetic heart valve withreduced reliance on imaging, and provide additional anchoring of theprosthetic valve, reducing the incidence of valve migration. Anotheradvantage is the delivery and implantation of a sutureless valveprosthesis as described herein.

The present disclosure also provides improved devices and methods forimplanting a prosthetic heart valve. In particular, improved minimallyinvasive methods and devices are provided for antegrade, percutaneous orfemoral transcatheter implantation of expansible prosthetic heart valveswithin or adjacent a valved anatomic site within the heart. Inparticular, the improved prosthetic heart valve devices and methods ofthe present disclosure provide more flexibility in the valve replacementprocedure, ensure accurate and precise placement of the prosthetic heartvalve with reduced reliance on imaging, and provide additional anchoringof the prosthetic valve, reducing the incidence of valve migration ormisalignment.

One method for deploying an aortic valve generally comprises inserting avalve delivery system between the ribs of the patient or subject intothe apex of the left ventricle, then delivering the valve prosthesis tothe site of the patient's diseased valve (transapical delivery). Anothermethod of deploying the aortic valve generally comprises gaining accessto the aorta through the femoral artery (femoral delivery).

Another method for deploying a pulmonary or a mitral valve generallycomprises inserting a valve delivery system into the jugular vein, thenguiding the system through the superior vena cava into the right atrium.The device can then be advanced into the right ventricle and to thepulmonary valve. Alternatively, the device can be advanced viatranseptal puncture into the left atrium, then advanced to the mitralvalve.

Yet another method for deploying a pulmonary or a mitral valve generallycomprises inserting a valve delivery system into the femoral vein, thenguiding the system through the superior vena cava into the right atrium,and advancing the device to the pulmonary or mitral valve as describedabove.

The valve delivery system or implantation device is of sufficient sizeand length to pass through a first opening in a patient's body (e.g., anaorta or a femoral artery or vein access point), through a patient'saorta, femoral artery or vein. The implantation device may alternativelyenter through a transthoracic port which provides access through thepatient's thoracoabdominal (e.g., intercostal) region and into the leftventricle at or near the apex. The transthoracic port according tovarious exemplary embodiments is one of an introducer, trocar, orcannular, as is generally known in the art.

At least one delivery sheath or catheter is advanced along a guidewirethrough and past the aortic, mitral or pulmonary valve. These methodsare described herein below, with reference to the prosthetic valve anddelivery device to be described. A skilled artisan, however, willappreciate that other methods of deploying the prosthetic valvedescribed herein can be used.

The access port includes one or more hemostasis valves or seals. Thehemostasis valve or seal is adapted to provide a blood tight sealagainst blood loss or leakage during the procedure, and can be used atthe apex, at the aorta, or in both locations. The port is configured toallow passage of the implantation device, catheter, or any tools ordevices to be delivered to the target site using the implantationdevice, while at the same time providing a blood tight seal againstblood loss or leakage. Such methods are well known to those havingordinary skill in the art.

The devices and methods described herein may be used with subjectsincluding humans and other mammals, including but not limited to rats,rabbits, pigs, dogs, sheep and horses.

A number of embodiments of the present invention will below be describedwith reference to the attached drawings. It should be understood thatthe various elements of any one particular embodiment may be utilized inone or more of the other embodiments, and thus combinations thereof arewithin the scope of the appended claims.

I. Prosthetic Valves

In a first aspect, and with initial reference to FIG. 1A, a valveprosthesis 2, which in a preferred embodiment is a prosthetic heartvalve, is provided. The valve prosthesis is configured to be placed in anative diseased valve of a subject, such as a native stenotic aortic,pulmonary or mitral valve, using a minimally-invasive approach such as abeating heart transapical procedure, or a retrograde transaorticprocedure. Such procedures are well known to persons having ordinaryskill in the art.

The sutureless prosthetic heart valve comprises a self-expanding supportframe, prosthetic valve leaflets (not shown in FIG. 1A) and one or morevalve claspers. The valve claspers may be positioned serially orconcentrically with the support frame. Both the support frame and thevalve claspers can be made from a shape memory material such that theycan be compressed to a radius which allows delivery through, forexample, arteries and veins, then expanded as needed for deployment andplacement of the valve in the appropriate position.

The valve claspers are movably connected to the support frame such thatthe valve claspers may be moved from a proximal or distal position fromthe support frame to a concentric position with the support frame.During delivery of the valve prosthesis, it is advantageous to have thevalve claspers positioned serially from the support frame. This allowsthe user to minimize the radius of the device which must be advancedthrough, for example, arteries and veins. The distance from which thevalve claspers may be serially displaced from the support frame ishighly variable, such that the valve claspers may be adjacent to thesupport frame, or potentially inches or feet away from the support frameduring the delivery procedure. In some embodiments, no part of the valveclaspers are physically fixed to the support frame, such as by weldingor otherwise adhering.

By “movably connected” (alternatively, “movably attached”) it isunderstood that while two structural elements may be in physical contactat any given time, they are not irreversibly connected or attached, suchas by welding or through an adhesive. For example, after deployment ofthe prosthetic valve as described herein, while the valve claspers arein physical contact with the prosthetic valve support frame, the valveclaspers are able to move longitudinally with respect to the supportframe. Also, portions of the valve clasper can move radially from thesupport frame. Regardless, the valve claspers remain movably connectedto the support frame.

As a result, when the support frame is in a compact or non-expandedcondition, the valve claspers can freely move along the longitudinalaxis in either a proximal or distal direction. In some embodiments, thevalve claspers are movably connected to the support frame in a mannerthat prevents the entire valve clasper from being radially displacedfrom the support frame, however, portions of the valve clasper can beradially displaced from the support frame as needed. When the supportframe is deployed or expanded within the native heart valve, the valveclaspers become sandwiched between the support frame and the nativevalve tissue, becoming at least partially, and may be fully immobilized.The valve claspers also function to hold the deployed prosthetic valvein place within the native valve.

As shown in FIG. 1A, which is representative, the valve prosthesiscomprises a support frame (e.g., a stent frame) 4 which comprises anouter surface 7 and defines a central orifice 9 about an axis (thelongitudinal axis denoted by dashed line 11 in FIG. 1A) along aninflow-outflow direction. The support frame is radially expandablebetween a compact or compressed condition and an expanded or deployedcondition.

The support frame can be a lattice design which can have differentshapes, including but not limited to, diamond and oval shape. A supportframe may have additional features, such as a plurality of flex-links 18as shown in support frame 16 depicted in FIG. 1C. Design of the supportframe with the plurality of flex links allows expansion of a portion ofthe valve support frame as illustrated in FIG. 1D.

The support frame can be self-expanding. In some embodiments, theself-expanding support frame can be comprised of a shape-memory metalwhich can change shape at a designated temperature or temperature range.Alternatively, the self-expanding frames can include those having aspring-bias. The material from which the support frame is fabricatedallows the support frame to automatically expand to its functional sizeand shape when deployed but also allows the support frame to be radiallycompressed to a smaller profile for delivery through the patient'svasculature. Examples of suitable materials for self-expanding framesinclude, but are not limited to, medical grade stainless steel,titanium, tantalum, platinum alloys, niobium alloys, cobalt alloys,alginate, or combinations thereof. Examples of shape-memory materialsinclude shape memory plastics, polymers, and thermoplastic materialswhich are inert in the body. Shape memory alloys having superelasticproperties generally made from ratios of nickel and titanium, commonlyknown as Nitinol, are preferred materials.

An alternative embodiment of the support frame is illustrated in FIGS.1C-1D. As shown, support frame 16 has a plurality of flexible links 18.The presence and arrangement of flexible links 18 allows the portion ofthe support frame on one side of the flexible links to expand orcompress independently of the portion on the other side of the flexiblelinks, as depicted in FIG. 1D. The functional significance of thisstructural feature is described in further detail below.

In an alternative embodiment, the support frame is not self-expanding,and may be expanded, for example, using a balloon catheter as is wellknown in the art.

In an exemplary embodiment, the valve prosthesis further comprises atleast one valve clasper, such as valve clasper 6 which is illustrated inFIG. 1A. Valve claspers may alternatively be referred to as sinuslocators, valve positioners, or valve hangers. In some embodiments,valve claspers are comprised of a shape-memory metal. In furtherembodiments, the shape memory alloy is Nitinol.

In an exemplary embodiment, the at least one valve clasper 6 is movablyconnected to the valve support frame 4. In another embodiment, the atleast one valve clasper 6 is movably connected to the valve supportframe 4 when the valve support frame 4 is in a compact condition priorto delivery and deployment. In yet another embodiment, the at least onevalve clasper 6 is not fixed to the valve support frame 4. It isunderstood that each valve clasper of a valve prosthesis describedherein is separate from the valve support frame. Thus, although a leasta portion of the valve clasper, e.g., the leg member, may be in contactwith or otherwise reversibly attached or connected to the valve supportframe, no part of the valve clasper is fixed, e.g., welded or otherwiseirreversibly adhered, to the valve support frame. Alternatively stated,the valve clasper, which may be in contract with or otherwise reversiblyattached to the valve support frame, is not irreversibly fixed to thevalve support frame.

The at least one valve clasper is comprised, in one embodiment, of au-shaped member 8 and two leg members, such as leg member 10 which isrepresentative. In some embodiments, each of two leg members 10 of thevalve clasper is positioned approximately parallel to the longitudinalaxis of the support frame and is attached to u-shaped member 8 by anapex 5. In some embodiments, each of the two leg members of the valveclasper has a first and second end, wherein each of the first ends ofthe two leg members are joined to the u-shaped member 8. An apex 5 ispresent between each leg and the u-shaped member. As used herein, anapex, e.g., apex 5, is defined as a vertex formed by the joining ofu-shaped member 8 and one leg member 10. In one embodiment, the vertexis curved. In another embodiment, the vertex is curved such that two legmembers 10 are approximately parallel to each other. In someembodiments, the second ends of the two leg members are free ends.

In additional embodiments, the second terminus or end of one or more ofthe leg members terminates in a detent 12 (also referred to as a foot orbarb), as shown in FIG. 2A. Detent 12 may be made of a shape memoryalloy such as nitinol. For some applications, the detents are orientedparallel to a longitudinal axis of the valve prosthesis, while for otherapplications, the detents are oriented to form an angle with respect tothe longitudinal axis. For example, the detents may be approximatelyparallel to the longitudinal axis of the valve prosthesis support framein the compact position and/or when the valve prosthesis is encased in asheath. Alternatively, the detents may form an angle with respect to thelongitudinal axis of the valve prosthesis or a leg member when the valveprosthesis is in an expanded condition. In other embodiments, thedetents can have varying lengths. In some embodiments, the leg membersmay have, for example, a zig-zag or coiled shape after deployment of thevalve prosthesis. The detents help to secure the valve claspers to thevalve support frame after the valve prosthesis is deployed in the nativevalve.

In some embodiments, the support frame has a length L and the legmembers are at least L in length. In other embodiments, the leg membersare equal to or less than length L.

It will be appreciated by those with skill in the art that the shape ofthe member joining the two leg members is not limited to being au-shape. The u-shaped member may have other shapes including, but notlimited to, rectangle, square, diamond, triangle, oval, circle, or acombination of these shapes. The u-shaped member may be of any shapethat allows it to engage and/or rest against the floor of the nativevalve sinus or adjacent to the commissure of the native valve leaflets.

The at least one valve clasper is movable along the longitudinal axis ofthe support frame. When the valve clasper is off-set from the supportframe, e.g., when the u-shaped member of the valve clasper is in aposition distal to the proximal end of the support frame and/or does notapproximately fully overlap with the support frame, this position isreferred to as the engagement position. In this position, u-shapedmember 8 of a valve clasper may extend radially from a leg member andthe longitudinal axis of support frame 4 in its compact condition.

In situ, when the valve clasper is in the nesting position, clasper apex5 is approximately adjacent to the distal end of support frame 4.Alternatively, the valve clasper is in its nesting position when atleast a portion of the u-shaped member is in contact or adjacent to thefloor of a native sinus or the commissures of the native leaflets of thevalve. In some embodiments, when a leg member, such as leg member 10,has a length L which is approximately equal to the length L of the valveprosthesis support frame, and a valve clasper, such as valve clasper 6,is in a position such that the leg members approximately completelyoverlap with the valve prosthesis support frame 4, this position isreferred to as the nesting position.

In a second aspect, as illustrated in FIG. 1B, a valve prosthesis 20comprises valve support frame 22 and a central orifice 32. Support frame22 is radially expandable between a compact condition and an expandedcondition. Support frame 22 has an outer or external surface 30 anddefines a central orifice 32 about an axis (the longitudinal axisdenoted by dashed line 34 in FIG. 1B). The longitudinal axis correspondsto the inflow-outflow axis. In some embodiments, the valve prosthesisfurther comprises a plurality of prosthetic valve leaflets (not shown inFIG. 1B).

In this embodiment, valve prosthesis 20 further comprises at least onevalve clasper 24. At least one valve clasper 24 comprises a u-shapedmember 26. The u-shaped member 26 has a curved portion at its proximalend connected to two straight portions, e.g., 28, each ending in a freeend, as seen in FIG. 1B.

In some embodiments, the straight portion of valve clasper 24 remainsstraight following deployment of valve prosthesis 20. In an alternativeembodiment, at least part of the straight portion of the at least onevalve clasper 24, which may be made of a shape memory material, mayhave, for example, a zig-zag or coiled shape after deployment of valveprosthesis 20 as shown in FIG. 2B for clasper 6.

The at least one valve clasper 24 is movably connected to support frame22 and movable along the longitudinal axis of support frame 22. Whenvalve clasper 24 is off-set from the support frame, e.g., when the freeends of valve clasper 24 are in a position proximal to the proximal endof support frame 22 and/or when valve clasper 24 does not fully overlapwith the support frame, this position is referred to as the engagementposition. In this position, at least one u-shaped member 26 of valveclasper 24 may extend radially from the longitudinal axis of supportframe 22 in its compact condition.

In situ, when valve clasper 24 is in the nesting position, at least aportion of at least one u-shaped member 26 is in contact with oradjacent to the floor of a native sinus or adjacent to the native valvecommissure.

In some embodiments, the plurality of valve claspers 6 or 24 movablyconnected to support frame 4 or 22, respectively, can be two, three,four, five, or more valve claspers, to accommodate different valvereplacement procedure or according to the anatomical structure of thenative valve that is to be replaced. In a particular embodiment, thenumber of valve claspers in the valve prosthesis is three.

In one embodiment, the plurality of valve claspers 6 movably connectedto support frame 4 can be joined to generate a single valve claspercomprising multiple u-shaped members 8 and multiple leg members 10.

The valve prostheses 2 and 20, as described herein can further comprisea plurality of prosthetic valve leaflets having surfaces defining areversibly sealable opening for unidirectional flow of a liquid throughthe prosthetic valve. The prosthetic valve can include three valveleaflets for a tri-leaflet configuration. As appreciated, mono-leaflet,bileaflet, and/or multi-leaflet configurations are also possible. Forexample, the valve leaflets can be coupled to the valve frame so as tospan and control fluid flow through the lumen of the prosthetic valve.

In some embodiments, the leaflets comprise synthetic material,engineered biological tissue, biological valvular leaflet tissue,pericardial tissue, cross-linked pericardial tissue, or combinationsthereof. In other embodiments, the pericardial tissue is selected frombut not limited to the group consisting of bovine, equine, porcine,ovine, human tissue, or combinations thereof. Prosthetic valve leafletsmay be sewed onto valve support frame 4 or 22 along a leaflet sutureline, e.g. suture line 19 as shown in FIG. 3A, which is a rolled-outview of a support frame. In other embodiments, valve leaflets are fixedonto support frame 4 or 22 by other comparable methods understood bythose with ordinary skill in the art.

In some embodiments, the support frame of valve prosthesis 2 or 20 is atleast partially covered by a covering. This is depicted in FIG. 3A for asupport frame 4 of valve prosthesis 2, wherein the support frame iscovered by a covering (graft covering) 15. Any suitable lightweight,strong, fluid impervious, biocompatible material may be utilized. Thecovering may be attached in any suitable manner and by any suitablemeans. For example, the covering may be reversibly attached orpermanently attached to the support frame. The covering may bepositioned on the external and/or internal surface of the valveprosthesis support frame. The covering may be attached to the frameutilizing sutures, staples, chemical/heat bonding and/or adhesive. Insome embodiments, the covering is a fabric. In further embodiments, thefabric is comprised of, for example, a material identified by atradename selected from Nylon®, Dacron®, or Teflon®, or is expandedpolytetrafluoroethylene (ePTFE), and/or other materials.

In one embodiment, the covering can further include a sealing material.The sealing material can be selected from the general class of materialsthat include polysaccharides, proteins, and biocompatible gels. Specificexamples of these polymeric materials can include, but are not limitedto, those derived from poly(ethylene oxide) (PEO), poly(ethylene glycol)(PEG), poly(vinyl alcohol) (PVA), poly(vinylpyrrolidone) (PVP),poly(ethyloxazoline) (PEOX) polyaminoacids, pseudopolyamino acids, andpolyethyloxazoline, as well as copolymers of these with each other orother water soluble polymers or water insoluble polymers. Examples ofthe polysaccharide include those derived from alginate, hyaluronic acid,chondroitin sulfate, dextran, dextran sulfate, heparin, heparin sulfate,heparan sulfate, chitosan, gellan gum, xanthan gum, guar gum, watersoluble cellulose derivatives, and carrageenan. Examples of proteinsinclude those derived from gelatin, collagen, elastin, zein, andalbumin, whether produced from natural or recombinant sources. Thematerials can be bioactive agents, including those that modulatethrombosis, those that encourage cellular ingrowth, through-growth, andendothelialization, those that resist infection, and those that reducecalcification. The covering may be on the inside and/or outside surfaceof the support frame, and may be disposed to partially cover the supportframe or to fully cover the support frame.

In one embodiment, at least a portion of at least one leg member 10 ofvalve clasper 6 is positioned between support frame 4 and the coveringon the surface of support frame 4. In this embodiment, the covering canfunction at least in part to movably connect valve clasper 6 to supportframe 4. In one embodiment, the at least one leg member 10 fixed at afirst end to the at least one u-shaped member 8, are movable parallel tolongitudinal axis 11, wherein at least a portion or substantially of theat least one leg member 10 can be positioned between the covering andsupport frame 4.

In one embodiment, the curved portion of the u-shaped member 26 of valveclasper 24 and/or a part of straight portion 28 is positioned betweensupport frame 22 and the covering on the surface of the support frame.In this embodiment, the covering can function at least in part tomovably connect valve clasper 24 to support frame 22. In one embodiment,the two straight portions of the valve clasper 24 is movable parallel tolongitudinal axis 32, wherein at least a portion or substantially of thevalve clasper is positioned between the covering and support frame.

In one embodiment, support frame 4 or 22 may be coated with a materialwhich promotes and/or supports tissue growth in the region in which thevalve prosthesis is deployed. Alternatively, the material which promotesand/or supports tissue growth may be imbedded or incorporated in thecovering.

In an alternative embodiment, shown in FIG. 3B, a support frame 14further comprises a plurality of engagement fasteners, such as fastener46. The engagement fasteners can be directly fixed on the support frameor can be manufactured as part of the support frame. Each set ofengagement fasteners are formed by several engagement fasteners that arearranged linearly along the longitudinal axis of the support frame. Eachengagement fastener may be a half circle shape, with the open sidefacing opposite directions in alternating engagement fasteners withineach set of engagement fasteners. The leg members of the valve claspersare inserted through the openings formed by each set of engagementfasteners.

FIGS. 3A and 3B also illustrate an embodiment wherein the support frameis covered with a covering 15.

During valve delivery, the support frame of prosthetic valve isinitially in a compact condition. In the embodiment where the valveclasper(s), which is/are also compact (not radially extending from thesupport frame), is/are movable between an engagement position and anesting position, the valve clasper(s) during valve delivery is/are inan engagement position where the valve clasper(s) is/are positioneddistally or proximally from the support frame. Once the valve prosthesisis at or near a desired in vivo position where a replacement valve isneeded, the valve claspers, such as valve claspers 6 a, 6 b, 6 c in FIG.4A, are moved to an open or expanded condition, for contact with andseating into a sinus of a native heart valve. Support frame 4 as shownin FIGS. 4A and 4B is then moved to an expanded condition. A pluralityof valve claspers 6 a, 6 b, 6 c movably connected to the support framein the compact condition, are shown in FIG. 4A as viewed from the top.FIG. 48 shows the plurality of valve claspers with support frame 4 inits expanded condition. FIG. 4C shows a support frame 14 havingengagement fasteners 46 a, 4Gb, 46 c wherein the support frame 14 is ina compact condition and the u-shaped members of valve claspers 47 a, 47b, 47 c are in an open or expanded condition for contact with andseating into a sinus of a native heart valve. FIG. 4D shows theplurality of valve claspers with support frame 14 in its expandedcondition. FIGS. 4E and 4F show support frame 14 having engagementfasteners 46 a, 46 b, 46 c, wherein support frame 14 is in a compactcondition (FIG. 4E) and an expanded condition (FIG. 4F).

FIG. 5A illustrates a valve clasper 6 movably attached to support frame4 relative to a native heart valve leaflet 30. When the support frame isin its compact condition, valve clasper 6 is movable from an engagementposition (FIG. 5A) to a nesting position (FIG. 5B), where valve clasper6 is in a nested or concentric arrangement with the support frame, andwherein u-shaped member 8 approximately contacts the sinus (e.g.,aortic, mitral or pulmonary sinus) of the native heart leaflet 30 (seeFIG. 5B). A prosthetic leaflet 36 is attached to support frame 4 andextends into the orifice of the prosthetic valve, to provide inconjunction with one or more additional prosthetic leaflets (not shown),a one-way valve in the orifice. As seen in FIG. 5C, after support frame4 is radially enlarged to an expanded condition, at least a portion ofnative valve leaflet 30 is sandwiched between u-shaped member 8 andsupport frame 4. Also shown in FIGS. 5A-5C is covering 15, which in someembodiments, may function in part to hold the leg member adjacent to thesupport frame.

FIGS. 5D-5F show support frame 14 with engagement fasteners 46 a, 46 b,46 c, wherein the valve clasper is above the native valve sinus and inan engagement position (FIG. 5D), the valve clasper has moved toward thevalve sinus to allow u-shaped member 11 to contact the native valvesinus (FIG. 5E) and support frame 14 has expanded radially so that atleast a portion of native valve leaflet 30 is sandwiched betweenu-shaped member 11 and support frame 14 (FIG. 5F).

In another embodiment, shown in FIGS. 5G-5I, valve clasper 24 is movablyconnected to support frame 22. In FIG. 5G, valve clasper 24, in anengagement position, is above the native valve and is radially expandedfrom support frame 22. As described above, when support frame 22 is inits compact condition, valve clasper 24 is movable from an engagementposition (FIG. 5G) to a nesting position (FIG. 5H), where valve clasper24 is in a nested or concentric arrangement with the support frame, andwherein u-shaped member 26 approximately contacts the sinus of nativeheart leaflet 30. As shown in FIG. 5I, support frame 22 is then radiallyenlarged to an expanded condition so that at least a portion of nativevalve leaflet 30 is sandwiched between valve clasper 24 and supportframe 22. Also shown in FIGS. 5G-5I is support frame covering 15, whichin some embodiments, may function in part to properly position the valveclasper relative to the support frame.

In an alternative embodiment, valve clasper 71 is fixed (e.g., adheredto or welded to) a support frame 73 of a valve prosthesis. FIG. 5J is atransverse view showing the valve prosthesis with fixed clasper 71 in anengagement position above the native valve. In FIG. 5K, the valveprosthesis is moved to a nesting position, while in FIG. 5L, supportframe 73 is expanded radially to an expanded condition, and valveclasper 71 is sandwiched between the native valve leaflet and supportframe 73.

The alternative embodiment, wherein the plurality of valve claspers,such as valve clasper 71 which is representative, are fixed to thesupport frame 44 of the valve prosthesis, is shown in FIGS. 6A-6C. Inthis embodiment, each valve clasper is directly fixed to the supportframe, for example, by welding. In other embodiments, the valve claspersare manufactured as part of support frame 44. The valve prosthesis,shown in FIG. 6A in a rolled out view, also shows a line 47 at whichprosthetic heart valves are secured to the support frame, and anoptional covering 48 on the support frame.

FIG. 6B is a top view of valve support frame 44 with valve clasper 71wherein valve clasper 71 is permanently fixed to the support frame andwherein support frame 44 is in a compact condition. FIG. 6C shows thesame valve support frame with clasper in which the support frame is inan expanded condition.

FIGS. 7A and 7B illustrate a sutureless valve prosthesis with movablyconnected claspers in situ. In FIG. 7A, support frame 90 is in a compactcondition and encased by sheath 96, and valve claspers 92 are in anested position prior to radial expansion of the support frame withinthe native valve. A portion of the implantation device is shown as 96.The engaging portion of the valve clasper, e.g., the u-shaped member orcurved portion, has contacted, or engaged, the native valve sinus. FIG.7B shows the same valve in which the support frame is in its expandedcondition, after valve delivery and deployment and after removal of avalve delivery device. Native heart valve leaflets 94 are sandwichedbetween the valve claspers and the support frame to facilitate anchoringof the valve prosthesis in the heart annulus. It is understood that thepositioning of the support frame in which native heart valve leafletsare sandwiched between valve claspers of a valve prosthesis and theprosthesis support frame is applicable to all coronary valves (i.e.,aortic, pulmonary, tricuspid and mitral). It is understood that in someembodiments, the number of valve claspers will equal of the number ofnative leaflets within the native valve being treated.

The valve prostheses as described herein may be used in various aspectsof implantation devices described herein or in any method or deviceknown by one with ordinary skill in the art to implant a valveprosthesis into a subject.

II. Implantation Devices for Delivery of a Prosthetic Aortic. Pulmonaryor Mitral Valve

In a third aspect, an implantation device for delivery of a valveprosthesis is provided. In a general embodiment, the implantation deviceis comprised of a valve prosthesis, such as valve prosthesis 2 describedabove, and a delivery device, now to be described.

In one embodiment of a implantation device and illustrated in FIGS.8A-8H and FIGS. 9A-9Q, implantation device 100 is designed, for example,for apical (antegrade) delivery of an aortic heart valve prosthesis,percutaneous delivery of a pulmonary valve prosthesis through thesuperior vena cava, or delivery of a mitral valve prosthesis orpulmonary valve prosthesis through the inferior vena cava. Theseminimally invasive procedures are readily understood by a person withordinary skill in the art.

In one embodiment of an implantation device and illustrated in FIGS.8A-8H and FIGS. 9A-9Q, implantation device 100 is designed for apicaldelivery of an aortic heart valve prosthesis. Implantation device 100includes a control unit, generally indicated in FIG. 8A by 250, and inone embodiment comprises several separate and independent controllers,described below.

Delivery device 100 comprises a first sheath 120 which fully orpartially encases a prosthetic valve support frame, e.g., support frame102, in a compact condition and a second sheath 130 which is locateddistal to first sheath 120 and encases at least one valve clasper, e.g.,valve clasper 106. In one embodiment, delivery device 100 furthercomprises a track wire controller 200 (alternatively called a trackcable controller) which is located proximal to first sheath 120. Inanother embodiment, delivery device 100 further comprises at least onetrack wire 150 (alternatively called a track cable) which extendsdistally from track wire controller 200 and may contact the proximalends of the valve clasper leg members. In one embodiment, track wirecontroller 200 comprises at least one release switch 210 which isattached to the proximal end of the at least one track wire. In someembodiments, delivery device 100 does not have a second sheath. Thedelivery device is designed with a hollow center to allow insertion of aguidewire 110 along which the delivery device may be advanced fordelivery of the valve prosthesis.

First sheath 120 is cylindrical in shape and is hollow. The first sheathmay be straight or curved. The length and flexibility of the firstsheath will vary according to the delivery method as would easily beunderstood by a skilled artisan. For example, delivery of the valveprosthesis through the femoral artery requires a flexible sheath whichis long enough to extend from the point of entry to the native valve inneed of treatment. Second sheath 130 is hollow and is mostly cylindricalin shape. The distal portion of second sheath 130 may have differentshapes, such as a curved cone, or a pointed tip. In one embodiment, thedistal end of second sheath 130 has an opening through with a guidewiremay pass.

In one embodiment, the at least one track wire 150 is in contact with atleast one valve clasper 106 such that the distal end of the at least onetrack wire 150 contacts the free end of a leg member 107 of valveclasper 106 (see FIGS. 9J-9L). In one embodiment, track wire 150 ishollow to permit, for example, insertion of one or more other cables orwires. In one exemplary embodiment, hollow track wire 150 encases alocking wire 220, seen best in FIG. 9J-9L, that extends from theapproximately proximal end of the control unit to the approximatelydistal end of a track wire 150. In another embodiment, the locking wireis fixed at its proximal end to a locking wire support 190 (FIG. 9M). Instill another embodiment, the locking wire comprises a locking member230 at its distal end (FIG. 9L).

As shown in detail in FIGS. 9I-9L, in some embodiments, track wire 150encases two of leg members, for example 107 a and 107 b in FIGS. 9K-9L,of two different, independent valve claspers 106 and locking wire 220.It will be appreciated by a person with skill in the art that thisarrangement of leg members and a locking wire having a locking memberresults in a friction fit of the components within the track wire, thussecuring leg members of two different valve claspers within a hollowtrack wire as long as the locking member of the locking wire is adjacentto two leg members at approximately the distal end of the track wire.

One having ordinary skill in the art can envision a variety ofmechanisms whereby each of the track wires, such as track wire 150, arefixed to the control unit, track wire controller 200 and/or releaseswitch 210. For example, the proximal ends of each of track wire 150 maybe welded or glued to the various components of the control unit.Alternatively, the proximal ends of track wire 150 may each be woundaround or threaded through the various components to allow greaterflexibility with respect to the lengths of track wire 150.

In some embodiments, the valve prosthesis support frame is at leastpartially covered by a covering and a track wire is disposed between thesupport frame and the covering, to movably secure the track wire to oneor more valve claspers and the support frame.

In one embodiment, the delivery device further comprises a valveprosthesis pusher wire 170 (alternatively called a pusher cable) havinga proximal end fixed to the control unit and a distal end for contactwith the proximal end of valve prosthesis 102. The details of variousembodiments of the pusher wire are presented in FIGS. 9M-9Q. Theimplantation device may comprise one, two, three, four or more valveprosthesis pusher wires. In another embodiment, the control unit of theimplantation device further comprises a pusher wire controller 165(alternatively called a pusher cable controller). In one embodiment,illustrated in FIG. 9M, the approximately proximal end of the valveprosthesis pusher wire 170 is fixed to pusher wire controller 165. Thepusher wire extends from the approximately proximal end of the valveprosthesis proximally to the pusher wire controller. The valveprosthesis pusher wire may be hollow or solid and may be made of wire,plastic or other suitable materials. In another embodiment, theimplantation device comprises a pusher wire support member which extendslongitudinally and distally from the pusher wire controller. The pusherwire support member may vary in length and functions to allow the userto apply pressure in a distal direction to the proximal end of the valveprosthesis, using the pusher wire controller. In one embodiment, thepusher wire support member is cylindrical in shape with a longitudinalaxis parallel to that of the first sheath. In another embodiment, thepusher wire support member is hollow. In yet another embodiment, atleast one pusher wire is located on the external side of the pusher wiresupport member. In an alternative embodiment, the at least one pusherwire is located on the internal surface of the pusher wire supportmember. In a further embodiment, at least a portion of valve prosthesispusher wire 170 is secured along its length to the pusher wire supportmember. This embodiment is shown in FIGS. 8F-8H. The pusher wire supportis fixed at its proximal end to pusher wire controller 165.

In some embodiments, the distal end of valve prosthesis pusher wire 170terminates in a pusher wire engager 175, for reversibly engaging theproximal end of the valve prosthesis. A skilled artisan will readilyunderstand that the valve prosthesis engaging member may comprise avariety of configurations, for example, those illustrated in FIGS.90-90, and may comprise, for example, one, two, three or more prongs.

One can envision the variety of mechanisms whereby each of pusher wiresare fixed to, for example, the control unit or pusher wire controller165. For example, the proximal ends of each of pusher wires may bewelded or glued to the various components of the control unit.Alternatively, the proximal ends of pusher wires may each be woundaround or threaded through the various components to allow greaterflexibility with respect to the lengths of pusher wires.

In one embodiment, the implantation device comprises a second sheath 130and a second sheath control cable 140 (central control cable) attachedat its distal end to the second sheath. In the embodiment shown in FIG.8F, second sheath 130 can take the form of a nose cone and is disposeddistal to the first sheath. Embodiments where a second sheath isconcentric with the first sheath are contemplated. The distal end ofsecond sheath control cable 140 may be attached to the proximal ordistal end of second sheath 130 or at a position between the proximaland distal ends of second sheath 130. In yet another embodiment, theproximal end of second sheath control cable 140 is fixed to a secondsheath controller 135. In another embodiment, the second sheath encaseseach of the plurality of valve claspers, e.g., valve claspers 106, in acompact condition. The second sheath controller functions to allow theuser to move the second sheath in a proximal or distal directionindependent of parts of the delivery device which are not fixed to thesecond sheath.

The control unit allows the user to independently control variouselements of the implantation device as described herein and shown inFIGS. 8A-8H. The control unit comprises a track wire control unit 200 toprovide for independent control by a user of track wire 150. The one ormore track wires in the device is attached at its proximal end to thetrack wire control unit. The distal end of at least one track wire 150can form a contact with a leg member of valve clasper 106. Track wirecontrol unit 200 comprises at least one release switch, such as releaseswitch 210, and the at least one track wire is fixed at approximatelyits proximal end to the at least one release switch. In anotherembodiment, implantation device 100 comprises two track wires, eachattached at its proximal end to a release switch, such as track wire 150fixed at its proximal end to release switch 210. In yet anotherembodiment, implantation device 100 comprises three track wires, eachattached at its proximal end to a release switch. In still anotherembodiment, implantation device 100 comprises four, five or more trackwires, each attached at its proximal end to the same or differentrelease switches. Each of the plurality of track wires 150 can form acontact at its distal end with one of the valve claspers 106 in theprosthetic valve, as will be described more fully below.

As noted above, at least prior to implantation, the implantation devicecomprises a first sheath, such as first sheath 120, that encases a valveprosthesis in its compact condition. In one embodiment, control unit 250of implantation device 100 may further comprise a first sheathcontroller 125, that in the exemplary embodiment shown in FIGS. 8A-8H,is fixed to first sheath 120. In this embodiment, first sheathcontroller 125 has two members fixed to opposite sides of theapproximately proximal end of the first sheath 120. It is understoodthat the first sheath controller 125 may have many shapes and one ormore members which allow a user to control movement of the first sheathin the proximal or distal direction. The first sheath controller maycomprise one, two, three or more members fixed to the first sheath 120.It will also be appreciated that the first sheath controller can also bepositioned proximal to the first sheath, for control of the sheath by auser's hands positioned at a proximal end of the implantation device.

Valve prosthesis support frame 102 encased in a compact condition withinfirst sheath 120 may be positioned anywhere along the longitudinal axisof first sheath 120. In one embodiment, valve prosthesis support frame102 is positioned at and fully encased within the approximately distalend of first sheath 120, as illustrated in FIG. 9A.

In one embodiment, second sheath control cable 140 is hollow. In anotherembodiment, a guidewire 110 can be fed through the hollow second sheathcontrol cable.

The control unit of the implantation device may comprise a singlestructural unit or multiple independent structural units. One embodimentof the control unit is illustrated in FIG. 8A. In this embodiment,control unit 250 comprises second sheath controller 135, locking wiresupport 190, track wire controller 200 with at least one release switch210, pusher wire controller 165 and first sheath controller 125, each ofwhich can be controlled independently of the others.

There are multiple alternative embodiments for means of reversiblyattaching the distal end of a track wire 150 to the proximal free end ofa valve clasper 106. These include locking mechanisms shown in FIGS. 10Band 10C and are well known in the art.

FIGS. 8A-8F also show the configuration of delivery device 100 as itwould be used in the positioning and deployment of a valve prosthesiswithin a native cardiac valve structure. FIG. 8A is delivery device 100as it is configured prior to inserting the device into the patient. Thevalve prosthesis is packed within the delivery device in a compactcondition such that the support frame is packed within the first sheathand the valve clasper(s) are packed within the second sheath which isdistal to the first sheath. As is normal practice, the guidewire isfirst introduced into the patient, e.g., into the femoral artery or intothe left ventricle through a transapical procedure, and advanced to theappropriate heart chamber, past or beyond the native cardiac valve inneed of repair.

FIG. 8B shows that both the second sheath and encased claspers are movedin a in a distal direction, usually past the native valve in need ofrepair. The second sheath controller 135 can be used to move the secondsheath, while track wire controller 200 can be used to move the claspersin concert with the second sheath. It is appreciated that in someembodiments, the delivery device may not comprise a second sheath.

FIG. 8C shows the release of the valve claspers from the second sheathby moving the second sheath in a distal direction while holding thevalve claspers stationary. It is notable that the orientation of thevalve claspers as such that when they are moved in a proximal directiontoward the native valve, they will “catch” on the sinus of the valvebetween the native leaflet and the valve annulus. For this reason, it isunderstood that delivery device 100 is useful in delivering anddeploying a valve prosthesis in a native valve wherever the device canbe advance through a native valve in which the native leaflets arecurved away from the delivery device. For example, device 100 is usefulfor implanting an aortic valve through a transapical approach, orimplanting a mitral valve when the device has entered the left atriumfrom the right atrium by way of a transapical puncture. Such methodswill be discussed more fully below.

FIG. 8D shows the delivery device in which the first sheath with encasedvalve support frame has been pushed in a distal direction until thedistal end of the valve support frame is about adjacent to the apex ofthe valve claspers. The length L of the valve support frame and thelength L of the valve clasper leg members are such that when the distalend of the support frame abuts the apex of the valve clasper, the valveframe with leaflets are in a position ready for deployment. At any timeduring the proximal and distal manipulations of the delivery device, theuser may also rotate the device as needed for positioning the valveclaspers.

FIG. 8E shows the valve prosthesis support frame in an expandedcondition. The first sheath was pulled in a proximal direction touncover the support frame, while the valve pushers and track wires atleast partially functioned to hold the valve support frame stationary.Here it shows that the first sheath was pulled in a proximal directionby pulling on the first sheath controller.

FIG. 8F shows that the release switches in the track wire controllerhave been pulled back in a proximal direction while other parts of thecontrol unit were held steady. Pulling the release switches in aproximal direction pulls the track wires in a proximal direction, whilethe locking wires and locking members are stationary, thus releasingfrictional force which held the leg members of the valve claspers withinthe track wires. At this point, the pusher wires can still be engagedwith the valve support frame, as shown in FIG. 8F.

FIG. 8G shows that the pusher wire controller has been pulled in aproximal direction, thereby pulling the pusher wires proximally and theyno longer are in contact with the valve support frame.

FIG. 8G also shows that the first sheath has been pushed in a distaldirection until it abuts the proximal edge of the second sheath. This isan optional step which may function to protect the surrounding tissuefrom possible damaging contact with the proximal edge of the secondsheath as the delivery device is removed from the body of the patient.

FIG. 8H shows that the second and first sheaths have been moved in aproximal direction by pulling back on the second sheath controller. Onecan appreciate that there are many ways in which the user may pull backon the individual components of the delivery device and the componentsof the delivery device control unit as the delivery device removed fromthe patient.

FIGS. 9B-9H provide cross-sectional views of delivery device 100 alongvarious positions indicated in FIG. 9A. FIGS. 9I-9L show detailed viewsof track member 150 and locking wire 107.

FIGS. 31A-31D illustrate delivery of a prosthetic valve wherein alocking wire and locking member is used to manipulate proximal anddistal movements of the valve claspers. FIG. 31A represents thepositioning of prosthetic support frame 960, claspers 952 a,b,c, hollowtrack wire 954 a,b,c, and locking member 956 a,b,c prior to delivery anddeployment of the prosthetic valve. The claspers are positioned distalto the valve support frame. Though not shown, support frame 960 is in acompacted form within a sheath as described above. Claspers 952 a,b,c,may also be compacted within a separate sheath. Also shown is theoptional presence of leg covering depicted by 958. The leg covering canbe made from, for example, a flexible fabric as discussed in more detailbelow. This embodiment may have three leg coverings to cover each pairof leg members which are packed within hollow track wires 954 a,b,c.

After claspers 952 a,b,c, are properly positioned within the nativevalve sinus, for example, at the floor of the native valve sinus,support frame 960 with prosthetic leaflets is pushed in a distaldirection to abut clasper apices 966 a,b,c, as shown in FIG. 31B. Thedevice provides the skilled practitioner with flexibility with respectto positioning the claspers and support frame prior to deployment. Insome cases, the claspers may be positioned over the edge of the nativeleaflet. After deployment and expansion of support frame 960, trackwires 954 a,b,c are pulled in a proximal direction to uncover the freeends of leg members and each of the detents (one of which is depicted inFIGS. 31C-31D as 962), which may be made of a shape memory material,reshapes to protrude from the longitudinal axis. These detents functionto create a more stable connection between the claspers and the deployedvalve support frame.

As shown in FIG. 31D, locking wires (FIG. 31C, 964 a,b,c) whichterminate in locking members 956 a,b,c, respectively, are then pulled ina proximal direction to disconnect from the deployed prosthetic valve.

Possible alternative embodiments for reversibly connecting a track wireto a valve clasper are shown in FIGS. 10A-10C, 17H-17J, 19A-19E,20A-20C, 21A-210 and 22A-22D and are appreciated by those with skill inthe art.

An alternative embodiment of the implantation device is an implantationdevice 180 for delivery of a prosthetic cardiac valve, as shown in FIGS.11A-11C. In one embodiment, a control unit 181 comprises a clasperposition controller 182 which may control rotational movement of valveclaspers 190 to position the valve claspers within the native valvesinus. In another embodiment, control unit 181 further comprises asecond sheath controller switch 183 (Step 1 Switch) which controlsmovement of a second sheath 191 (nose cone), a first sheath controllerswitch 184 (Step 2 Switch) which controls movement of a first sheath192, and a valve release switch 186 (Step 3 Switch) which moves firstsheath 192 to uncover the prosthetic valve 193. The first sheath encasesa valve prosthesis support frame 195 and at least one track wire 197. Asecond sheath control cable 198 is also shown. Prior to deployment ofthe valve prosthesis, the delivery device is configured as shown in FIG.11A. After radial expansion of valve prosthesis support frame 195, butprior to removal of the delivery device from the patient, the deliverydevice is configured in situ as shown in FIG. 11B.

In another embodiment, control unit 181 further comprises at least onerelease switch 187. Control unit 181 is shown in greater detail in FIG.11C.

III. A First Implantation Device for Retrograde Delivery of an AorticValve Prosthesis

In a fourth aspect, an implantation device 300 for delivery of an aorticvalve prosthesis through the femoral artery is provided. Implantationdevice 300 can comprise the valve prosthesis as shown in FIG. 1B anddescribed above, wherein each valve clasper comprises a u-shaped member.

In one embodiment of a delivery device and illustrated in FIG. 12A,implantation device 300 can be used for femoral delivery of an aorticheart valve prosthesis. In an alternative embodiment, implantationdevice 300 may provide for apical delivery of a mitral valve.

Implantation device 300 includes a control unit, generally indicated inFIG. 12A by 326, and in one embodiment, comprises several separate andindependent controllers, described below. Control unit 326 also includesa track wire controller 342, at least one track wire 344, and a firstsheath 308. The implantation device shown in FIG. 12A has three trackwires.

In one embodiment, first sheath 308 at least partially encases valveclasper 324 and track wires 344. A first sheath controller 338 is fixedto the proximal end of first sheath 308. First sheath controller 338 canfacilitate both proximal and distal (longitudinal) movement of the firstsheath, and, optionally, rotational movement of the track wires andattached claspers to allow for proper positioning of the claspersrelative to the native valve leaflets.

The control unit allows the user to independently control variouselements of the implantation device as described herein and shown inFIG. 12A. The control unit comprises a track wire controller 342 toprovide for independent control by a user of track wire 344 a. The oneor more track wires in device 300 is attached at its proximal end to thetrack wire controller. The distal end of at least one track wire, suchas 344 a, can form a contact with a free end of valve clasper 324. Trackwire controller 342 comprises at least one release switch 320, such asrelease switch 320 a, and the at least one track wire, such as trackwire 344 a, is fixed at approximately its proximal end to the at leastone release switch, such as release switch 320 a. In another embodiment,implantation device 300 comprises two track wires 344 a and 344 b, eachattached at its proximal end to a release switch, such as track wire 344b fixed at its proximal end to release switch 320 b. In yet anotherembodiment, implantation device 300 comprises three track wires, eachattached at its proximal end to a release switch. In still anotherembodiment, implantation device 300 comprises four, five or more trackwires, each attached at its proximal end to the same or differentrelease switches. Each of the plurality of track wires can form acontact at its distal end with at least one of the valve claspers in theprosthetic valve, as will be described more fully below. Each of theplurality of track wires may encase one or more straight portions of aclasper leg member and/or a locking wire as depicted in FIGS. 12C-12D as322 a,b,c.

Implantation device 300 may further comprise a track wire support 356which may encase the plurality of track wires 344.

In another embodiment, the at least one track wire is in contact withthe at least one valve clasper such that the distal end of the at leastone track wire contacts the valve clasper (see FIG. 13B). The valveclasper of implantation device 300 comprises a u-shaped member having acurved portion and two straight portions. Each of the straight portionsterminate in one free end. As shown in FIG. 13B, track wire 344 encasesthe straight portion and free end of two individual valve claspers 324a,b. In an embodiment, the track wire is hollow to permit, for example,insertion of one or more other cables or wires. In one exemplaryembodiment, a hollow track wire encases a locking wire 328, as shown inFIGS. 13B and 13C, that extends from the approximately proximal end ofthe control unit to the approximately distal end of a track wire 344. Inanother embodiment, the locking wire is fixed at its proximal end to alocking wire support. In still another embodiment, the locking wirecomprises a locking member 329 at its distal end (FIGS. 13B and 13C).

As shown in detail in FIG. 13B, in some embodiments, track wire 344encases a locking wire and two straight portions of two different,independent, adjacent valve claspers, such as valve clasper 324. It willbe appreciated by a person with skill in the art that this arrangementof valve claspers and a locking wire having a locking member results ina friction fit of the components within the track wire, thus securingthe straight portions of two different valve claspers within a hollowtrack wire as long as the locking wire with the locking member isapproximately adjacent to two leg members at the distal end of the trackwire. Movement of the track wire independent of the locking wire, suchthat the track wire is moved proximally in relation to the locking wire,results in loss of the friction fit, allowing the valve claspers to bereleased from the hollow track wire.

One having ordinary skill in the art can envision a variety ofmechanisms whereby each of the track wires, such as track wire 344 a,are fixed to the control unit, track wire controller 342 and/or releaseswitch 320. For example, the proximal ends of each of track wire 344 maybe welded or glued to the various components of the control unit.Alternatively, the proximal ends of track wire 344 may each be woundaround or threaded through the various components to allow greaterflexibility with respect to the lengths of track wire 344.

In some embodiments, a valve prosthesis support frame, such as valveprosthesis support frame 305, is at least partially covered by acovering and the valve clasper is movably fixed to the valve prosthesissupport frame by threading the free ends of valve clasper 324 throughthe covering. In this configuration, the curved portion of the valveclasper is external to support frame covering.

Implantation device 300 further comprises a second sheath, such assecond sheath 310, which encases a valve prosthesis support frame in itscompact condition. Implantation device 300 still further comprises asecond sheath control cable 334 which is fixed at its distal end to aportion of the internal surface of the distal end of second sheath 310.In yet another embodiment, the approximately proximal end of secondsheath control cable 334 is fixed to a second sheath controller 336. Thesecond sheath controller facilitates the user in moving the secondsheath control cable, and thereby the second sheath, in a proximal ordistal direction. This movement may or may not be done independently ofother parts of the implantation device.

In one embodiment, second sheath control cable 334 is hollow. In yetanother embodiment, a guidewire can be fed through the hollow secondsheath control cable.

In another embodiment, the second sheath at least partially encases thecurved portion of each of valve claspers 324 in a compact conditionprior to deployment of the valve prosthesis.

FIG. 13C shows the embodiment wherein the free ends of the valveclaspers terminate in a detent 349 a,b, which can be made of a shapememory material. In this drawing, after release of the valve claspers324 a,b from the track wires, the detents coil. This reshaping of thedetents provide a structural component which can function to enhancesecuring of the claspers of the deployed valve prosthesis to the supportframe.

FIGS. 14A and 29B-29H show manipulations of implantation device 300 asit is used to deliver and deploy a valve prosthesis in the patient. FIG.14A shows the implantation device prior to insertion into the patient.Second sheath 310 is then advanced through, for example, the femoralartery to the aortic valve until the second sheath, which encases valveprosthesis support frame 305 in a compact condition, is positionedwithin the native valve. This initial positioning of the support framemay be done using an imaging system as is understood by the skilledartisan.

FIG. 14B illustrates the implantation device wherein the u-shapedmembers of the valve claspers have been released from the second sheathand the track wires have been pushed in a distal direction. The trackwires can be pushed in a distal direction by moving the track wirecontroller in a distal direction. Notably, in this embodiment, acovering covers the valve prosthesis support frame and the straightmembers of each valve clasper have been threaded through the proximalend of the covering such that the curved portion of the valve clasperwhich will engage the native valve sinus, is positioned external to thesupport frame covering. Accordingly, as the track wires are pushed in adistal direction, the valve claspers remain movably attached to thedistal end of the valve prosthesis support frame, however, the distalend of each valve clasper can radially extend from the compact supportframe.

FIG. 14C shows that second sheath 310 is pushed in a distal direction toonly partially uncover the valve prosthesis support frame. The partialuncovering is an optional step which may function to minimize undesiredmovement of the support frame out of the targeted position.Alternatively, the second sheath may be pushed in a distal direction tofully undercover the valve prosthesis support frame. The second sheathcan be moved distally by pushing second sheath controller 336 distally.

FIG. 14D shows that second sheath 310 has been pushed in a distaldirection to fully uncover the valve prosthesis support frame, allowingthe support frame to fully expand to its expanded condition. At thistime, the valve claspers are positioned concentric to the support frame,and the native valve leaflets are disposed between the valve claspersand the support frame, thereby further anchoring the valve prosthesiswithin the native valve.

IV. A Second Implantation Device for Femoral Delivery

In a fifth aspect, and with reference to FIG. 15A, an implantationdevice 400 comprising a valve prosthesis support frame 440 with at leastone clasper 425 which is movably connected to the valve prosthesis, anda delivery device comprising a control unit 410, a first sheath 410encasing the valve prosthesis support frame 440 in a compact condition,a second sheath 430 encasing the valve claspers in a compact condition,a first sheath control cable 411 fixed to a first sheath control switch445, and a second sheath control cable 412 fixed to a second sheathcontrol switch 435, is provided. Embodiments of a valve prosthesis withvalve claspers is described above. Methods for using the implantationdevice for femoral delivery of an aortic valve prosthesis is illustratedin FIGS. 15A-15C and discussed in more detail below.

The control units for the above-described delivery devices function atleast in part to facilitate independent control of the variouscomponents of the implantation device, including track wires, pusherwires, and/or first and second sheaths. Persons having ordinary skill inthe art understand that each of the various components (e.g., firstsheath, second sheath, track wires, locking wires, pusher wires) whichmay be moved proximally or distally along the longitudinal axis of theimplantation device, can be attached directly or indirectly to thecontrol unit of the implantation device. The above described embodimentsprovide examples of how the control unit elements are moved by pushingor pulling a portion of the control unit in a distal or proximaldirection, respectively. Such pushing and pulling is accomplished byusing, for example, a switch connected to a wire, or pushing or pullinga handle which may be part of, for example, a sheath.

In an alternative embodiment, the control unit may comprise one or moredial portions wherein individual movable components of the implantationdevice (e.g., first sheath, second sheath, track wires, locking wires,pusher wires) may be moved proximally or distally by rotating a dial. Inthis embodiment, separate sections of the control unit may be connectedor coupled such each section includes complementary threads for anadjacent section such as to allow for threaded engagement of the twosections. Accordingly, clockwise or counterclockwise rotation of onethreaded section will produce distal or proximal longitudinal movementof that section relative to an adjacent threaded section. It isunderstood that a single implantation device control unit may compriseboth rotational control elements such as the threaded sections, andcontrol elements such as switches and handles that are moved along thelongitudinal axis.

V. Alternative Valve Embodiments

In an alternative embodiment of the valve prosthesis support frames asthey may be used with the implantation devices disclosed herein, FIG.16A depicts a valve prosthesis support frame which can be manufacturedin separate units to make a single support frame 95 comprising a distalportion 101 and a proximal portion 103 wherein distal portion 101 canexpand independently of proximal portion 103 (see FIG. 16A).Alternatively, as shown in FIG. 16B, a single support frame 97 ismanufactured as a single unit in such a way that a distal portion 105can expand independently of a proximal portion 107. Accordingly, asshown in FIG. 16C, a first sheath 112 is moved in a proximal directionto expose only a portion of valve prosthesis 95 prior to exposing andexpanding the full valve prosthesis support frame. Similarly, a firstsheath can be moved in a proximal direction to expose only a portion ofvalve prosthesis 97 prior to exposing and expanding the full valveprosthesis support frame.

It is understood that a prosthetic valve having support frame 16 asillustrated in FIGS. 1C-1D may serve as an exemplary embodiment of asupport frame which can partially expand upon uncovering of only aportion of the support frame.

VI. Alternative Valve Clasper Embodiments

An alternative embodiment of the valve claspers is illustrated in FIGS.17A-B. In these embodiments, each of a plurality of valve claspers isfixed to another to form a clasper multiplex unit 800. Clasper multiplexunit 800 further comprises a plurality of leg members. It is understoodthat there may be two, three, four or more u-shaped members attached totwo, three, four or more leg members to form the clasper multiplex unithaving a plurality of valve claspers. As an example, and illustrated inFIG. 17 A, u-shaped members 802 a and 802 b are each attached to legmember 810 a, through apex 806 b and 806 c, respectively. Similarly,u-shaped members 802 b and 802 c are each attached to leg member 810 b,through apex 806 d and 806 e, respectively. In some embodiments, theproximal end of each leg member 810 a,b,c can have a hole, asillustrated in FIG. 17A, 825 a,b,c. In other embodiments, there is not ahole through the proximal end of each leg member.

FIG. 17A shows an embodiment wherein leg members 810 a,b,c are designedto have a plurality of barbs, such as barbs 820. These barbs mayfunction to facilitate stabilization of the valve prosthesis afterdeployment within the native valve. In other words, upon deployment ofthe prosthetic valve, the barbs protrude such that at least one barbpierces the support frame covering and/or the leg covering if present.In a preferred embodiment, the support frame covering is attached (e.g.,sewed) to the support frame. The leg covering, if present, is attached(e.g., sewed) to the support frame covering. Accordingly, if the barbsof the valve claspers pierce the support frame covering and/or the legmember covering, this will result in anchoring the valve clasperstructure to the support frame structure. Alternatively, the barbs maybecome embedded within the support frame covering and/or the leg membercovering to facilitate anchoring of the valve clasper to the supportframe structure. It is understood that such anchoring elements may haveany of a number of different shapes. These anchoring elements may or maynot be made of a shape memory metal. The term, barb, may encompass anystructural element which protrudes from the clasper and which mayfunction to facilitate anchoring of the valve prosthesis within thenative valve of the patient. It is understood by the ordinary artisanthat the pattern of barbs on a leg member can be varied. For example, aseries of barbs may be present along a line on one side of a leg member834 as shown in FIG. 17C. A portion of the clasper u-shaped member isdepicted as 832. Protrusion of barbs 836 upon deployment of theprosthetic valve is shown in FIG. 17D. In one embodiment, one or moreleg members, with or without barbs 835 is designed to have an opening833 as depicted in FIG. 17E. A portion of the clasper u-shaped member isdepicted as 831. The size and shape of this opening may vary and isdesigned to make the clasper more durable. The spacing between each barbmay be uniform or varied. Alternatively, as shown in FIG. 17F, each of aseries of barbs 839 on a leg member 838 may be located on alternatingsides of the leg member. A portion of the clasper u-shaped member isdepicted as 837. The barbs may be staggered relative to one another.FIG. 17G shows optional features including a hole 844 and protrusions843, the size and shape of each which may vary according to the requiredfunctions. In FIGS. 17G-17H, the leg member and barbs are depicted by841 and 842, respectively and a portion of the clasper u-shaped memberis shown as 840.

In another embodiment, a clasper multiplex unit 850, as shown in FIG.17B, comprises a plurality of u-shaped members, e.g. 852 a,b,c, whichare attached or fixed to each other via apices 856 a-f. Claspermultiplex unit 850 does not comprise leg members. In some embodiments,the clasper multiplex unit may comprise holes as shown in FIG. 17B as875 a,b,c. Each hole may provide a point of attachment for a removableleg member. In some embodiments, clasper multiplex unit 850 does nothave these holes.

FIGS. 17K-17M provide alternative embodiments with respect to the legmembers of clasper multiplex units. In each of these examples, the legmembers of the clasper multiplex unit are short so as to provideincreased flexibility to the functional features of the claspers. FIG.17K illustrates a leg member connected to a flexible wire or othersimilar durable filament structure 871.

The clasper multiplex units and components thereof as described aboveand illustrated in FIGS. 17A-17M may be comprised of a shape memorymetal, such as Nitinol. The u-shaped members may be capable of radialexpansion away from the central axis of the unit.

FIGS. 18A-18B illustrate how a clasper multiplex unit may be positionedrelative to a valve support frame. The clasper multiplex unit is notpermanently fixed to valve support frame 892. The clasper multiplex unitis movably connected to the valve support frame such that the claspermultiplex unit may move in a proximal and/or distal direction along thelongitudinal axis of the valve support frame. FIGS. 18A-18B also showthe valve prosthesis with a covering 890 on the internal face of valvesupport frame 892. In some embodiments, the covering may be on theexternal face of the valve support frame.

FIGS. 18A-18B show an alternative embodiment wherein the valveprosthesis further comprises a leg covering 888. FIG. 18A shows a legmember 882 which has a plurality of barbs, e.g., barbs 884. FIG. 18Bshows a leg member 895 having a different style of barb as depicted by896. It is understood that leg covering 888 may or may not be present.The leg covering is preferably made of a flexible material, such thateach of the barbs may easily pierce the leg covering upon deployment ofthe prosthetic valve. As with the prosthetic valve frame, any suitablelightweight, durable, flexible, fluid impervious, and/or biocompatiblematerial may be utilized for the leg covering. The leg covering may beattached to the frame utilizing sutures, staples, chemical/heat bondingand/or adhesive. In some embodiments, the covering is a fabric. Infurther embodiments, the fabric is comprised of, for example, a materialidentified by a tradename selected from Nylon®, Dacron®, or Teflon®, oris expanded polytetrafluoroethylene (ePTFE), and/or other materials.

Delivery of a prosthetic heart valve as using the embodimentsillustrated in FIGS. 18A-18B wherein the implantation device utilizesmultiplex claspers as shown in FIGS. 18A-18B, may require alternativemethods for connecting and disconnecting the multiplex claspers to andfrom the implantation device (e.g., track wires). While a person havingordinary skill in the art could envision several methods of connectionand disconnection, alternative embodiments are provided in FIGS.17H-17J. For example, as shown in FIG. 17H-17I, protrusions 843 mayinsert into an opening in a wire 846 as a means for connecting the legmember of multiplex clasper 840. This connection is stabilized whenencased in a hollow track wire such as track wire 847 (FIG. 17I). FIG.17J illustrates yet another structure for connecting and disconnectingthe leg member of a multiplex clasper to the appropriate element of theimplantation device. FIG. 17J shows that a flexible tension element 848is fed through a hole at the proximal end of the multiplex clasper legmember and wrapped around the distal end of a lock and release element849. Flexible tension element 848 is pulled in a proximal direction tosecure the leg member to the appropriate element of the implantationdevice (a wire 851 encased by a track wire 853 in FIG. 17J).

VII. Alternative Clasper Release Mechanisms

FIGS. 19-22 illustrate alternative embodiments for the reversibleattachment of the implantation device to valve claspers. FIGS. 19-20show the use of a flexible tension element which runs along thelongitudinal length of a lock and release element to provide a means ofreversibly attaching a clasper multiplex unit to a valve implantationdevice. As shown in FIG. 19A, prior to connecting the valve implantationdevice to the leg members of a clasper multiplex unit, flexible tensionelement 902 extends along and beyond lock and release element 904.Flexible tension element 902 and lock and release element 904 are atleast partially encased within a hollow track wire 906. In this example,the tension and lock and release elements are attached to the proximalend of a leg member 908 of a multiplex clasper unit. FIG. 19B shows theproximal end of lock and release element 904 and tension element 902,which may be attached to the implantation device control unit by anymeans which would allow independent control of each of the two elements.

A method which may be used to attach the clasper multiplex unit to thecontrol unit of a valve implantation device is depicted in FIGS. 19C-D.The attachment is performed prior to packing the valve prosthesis intothe implantation device. A loop 912 formed at the distal end of flexibletension element 902 is fed through a hole 910 at the free end of a legmember 908 of a clasper multiplex unit. Lock and release element 904 isthen moved in a distal direction independently of the flexible tensionelement until the distal end of the flexible tension element is pushedthrough loop 912 (FIG. 19D). Flexible tension element 902 can be pulledin a proximal direction in order to tighten and secure the connectionbetween leg member 908 and the implantation device. Hollow track wire906 is then moved distally to cover the majority of flexible tensionelement 902 and lock and release element 902, such that the distal endof track wire 906 is approximately adjacent to the proximal end of legmember 908 (see FIG. 19E).

Release of a clasper multiplex unit leg member is illustrated in FIGS.20A-C. As seen in FIG. 20A-B, lock and release element 904 is moved in aproximal direction independently of flexible tension element 902. FIG.20C shows how track wire 906, flexible tension element 902 and lock andrelease element 904, are moved together in a proximal direction. Due tothe flexibility of the flexible tension element, flexible tensionelement 902 is easily removed from hole 910 of leg member 908.

Yet another structure whereby a valve implantation device is attached toleg members of a clasper multiplex unit is illustrated in FIGS. 21-22.FIG. 21A-C shows how a flexible leg could be interlocked with a tensionelement. In this embodiment, the tension element may or may not be madeof a flexible material. As shown in FIG. 21A, flexible leg 920,comprises an apex member 928 which interlocks with tension element 922at tension element apex member 924. Flexible leg 920 and tension element922 are reversibly connected via this interlock prior to delivery, whenthe valve prosthesis is packed into the implantation device. Afterinterlocking the flexible leg and the tension element, a hollow trackwire, e.g., track wire 926, is moved distally to cover the interlockedportion as well as the distal portion of the flexible leg as shown inFIG. 21B. The track wire prevents the flexible leg from radiallyexpanding prior to and during delivery of the valve prosthesis. FIG. 21Cpresents a depiction of the proximal end of this attach-and-releaseembodiment. It is understood that tension element 922 and track wire 926are attached at their proximal ends to a point near the proximal end ofthe valve implantation device or to the valve implantation devicecontrol unit is such a manner as to allow independent longitudinalmovement of the tension element and the track wire.

FIGS. 22A-C show how flexible leg 920 is released from tension element922. First, the track wire may be pulled back in a proximal direction touncover the proximal end of the flexible leg (see FIG. 22A). Due to theflexible nature of flexible leg 920, pulling tension element 922 in aproximal direction causes flexible leg 920 to straighten at its apex928, as shown in FIGS. 22B-22C. The user may then pull track wire 926and tension element 922 in a proximal direction to allow release offlexible leg 920.

The flexible tension element may be, for example, a monofilament,multifilament or braided multifilament structure. Examples may includewires, threads or monofilaments such as that used in surgical sutures.Monofilaments can be made from natural sources such as catgut, silk orlinen, or they may be synthetic. Monofilament nonabsorbable sutures maybe made from, for example, nylon or polypropylene. The flexible tensionelement can be comprised of a shape memory material. Persons of ordinaryskill in the art will be able to choose appropriate materials forflexible tension elements based on characteristics such as tensilestrength, knot strength, elasticity, memory or stiffness and tissuereactivity.

In one embodiment, the flexible leg as described above and shown inFIGS. 21-22, may function as the clasper leg, wherein, for example,flexible leg 920 would be attached to hole 875 of clasper multiplex unit850 (see FIG. 17B). In another embodiment, the flexible leg may functionto attach a clasper leg to the tension element of the valve implantationdevice. For example, flexible leg 920 in FIG. 21A, could be interlockedat its proximal end with tension element 922, and attached at its distalend to the proximal end of clasper leg 810 of clasper multiplex unit 800(see FIG. 17A). In yet another embodiment, the flexible leg may beattached at its distal end directly to the valve support frame, forexample, at a commissure post on the frame.

VIII. Method for Deploying an Aortic Valve Prosthesis

In a sixth aspect, a method for delivering the valve prosthesisdescribed herein in a compressed form or compact condition to the heartusing implantation device, such as implantation device 100, is provided.

FIGS. 24A-24H show one procedure for delivering a valve prosthesis tothe aortic valve, positioning and deploying the valve prosthesis. One ofskill in the art will readily understand the application of the deliverymethod and device manipulations as they apply to, for example,implantation device 100. FIGS. 24A-24H are cross-sectional views throughthe left side of a patient's heart showing the acts performed indelivering the support structure using a transapical approach. It shouldbe noted that such figures as provided herein are schematic in natureand thus do not necessarily depict a precise representation of thedelivery process. For example, the patients ribcage is not shown forillustrative purposes and the size of the sheaths used with the deliverysystems have been altered somewhat in order to better illustrate theprocedure. One of ordinary skill in the art, however, will readilyunderstand the range and types of sheaths and catheters that can be usedto implement the depicted procedure. FIG. 23 shows insertion of anintroducer 134 into the patient.

FIGS. 24A-24H illustrate transapical implantation of an aortic valveusing an implantation device 600. Implantation device 600 shares manyfeatures with implantation device 100. Implantation device 600 isadvanced along the guidewire until second sheath (nose cone) 610 isposition past (distal to) the native heart valve. A second sheathcontroller switch within a control unit 670 is used to move secondsheath 610 (nose cone) distally, to allow u-shaped members 615 of theprosthetic valve claspers to extend radially, as shown in FIG. 24B. Themethod as described below and illustrated in FIGS. 24A-24H can be usedwith delivery device 100 and valve prosthesis 2 described above.

A first sheath controller switch in control box 670 is used to movefirst sheath 620 in a distal direction and partially through the nativeheart valve, as shown in FIG. 24A. First sheath 620 encases supportframe 625 of the valve prosthesis in a compact condition. As firstsheath 620 is moved distally toward the native heart valve, the valveclaspers remain stationary. A native valve leaflet is shown by 645.

FIG. 24B shows that second sheath 610 is pushed in a distal direction touncover valve claspers 615. Second sheath 610 can be moved in a distaldirection by pushing distally a second sheath control cable 655 that isattached at its distal end to the second sheath and at its proximal endto the control unit. Once uncovered, the valve claspers extend radiallyabove the native valve.

FIG. 24C shows that the control unit has been manipulated to pull thevalve claspers in a proximal direction until the u-shaped members ofvalve claspers contact or otherwise engage the native valve, such asabutting the floor of the native valve sinus or the base of the nativevalve leaflets. The valve claspers are moved proximally by pulling thetrack wires in a proximal direction as described above.

FIG. 24D shows that first sheath 620 has been advanced until the distaledge of the first sheath, and therefore the distal edge of support frame625 abuts the apex of the valve claspers. Accordingly, the support frameis now in the proper position within the native valve for expansion ofthe support frame and implantation of the valve prosthesis. It isunderstood that prior to expansion of the support frame, theimplantation device can still be manipulated to make minor adjustmentsof the valve prosthesis in terms of distal, proximal and rotationalpositioning.

FIG. 24E shows that first sheath 620 has been pulled back in a proximaldirection while holding the support frame stationary in order to uncoversupport frame 625 allowing support frame 625 to expand radially alongthe track wires which extend from leg members of the valve claspers andallow the valve claspers to clasp onto leaflets, such as leaflet 645, ofthe native valve, as shown in FIG. 24E. As can be seen, native valveleaflets, e.g. 645, are sandwiched between valve clasper 615 and supportframe 625. Track wires, e.g., track wire 630, are still in contact withthe valve claspers. Track wires help to guide the correct radialposition (commissure to commissure) of the valve prosthesis when itexpands or deploys.

FIG. 24F shows that the track wires have been pulled back in a proximaldirection to release the valve claspers after ensuring that the valveprosthesis is properly placed. The track wires may be detached from theleg members of the valve claspers by pushing or pulling back on releaseswitches.

FIG. 24G shows that first sheath 620 has been pushed in a distaldirection to abut the proximal edge of second sheath 610. This step isoption and functions to protect surrounding tissue from possible damageby the proximal edge of the second sheath as the delivery device isremoved from the patient. The implantation device is pulled in aproximal direction along the guidewire to remove the device from thepatient, leaving the deployed valve prosthesis in place.

FIG. 24H shows removal of the implantation device from the heart whileleaving the prosthetic valve in place.

In an alternative embodiment, first sheath 620 is moved in a proximaldirection to expose only a portion of the valve prosthesis supportframe. A valve support frame as depicted in FIGS. 1C-1D could beimplemented for this procedure and encased in first sheath 620.

When the valve prosthesis is fully deployed in the annulus of the nativeheart valve, the native valve leaflets become sandwiched in between theu-shaped members and the leg members of each of valve clasper 615. Thisprovides additional anchoring of the valve prosthesis within the heart.

IX. Method for Deploying a Mitral Valve Prosthesis Via Inferior VenaCava Delivery

In a seventh aspect, a method for delivering a valve prosthesis in acompressed form or compact condition to the heart using an implantationdevice 100 via delivery through the inferior vena cava is provided. Inone embodiment, the valve prosthesis is a mitral valve prosthesis.

The method of delivering a mitral valve via the inferior vena cava usingimplantation device 100 is illustrated in FIGS. 25A-25L. Theimplantation device can be inserted into the femoral vein of the patientthen advanced to the inferior vena cava as shown in FIG. 26. Prior toinserting the implantation device into the patient, a guidewire 110 canbe introduced into the femoral vein and then advanced using imagingthrough the inferior vena cava, then advanced through the intra-atrialseptum with a needle according to methods known to a skilled artisan,into the left atrium and distal through the mitral valve into the rightventricle. Implantation device 100 is then advanced along guidewire 110through the intra-atrial septum and through the mitral valve into theleft ventricle.

FIG. 25B shows the implantation device prior to be advanced alongguidewire 110 through the transeptal wall into the left atrium.

FIG. 25C shows advancement of the implantation through the transeptalwall into the left atrium. An embodiment of the first sheath, shown inFIGS. 25A-25K as 122, illustrates that the first sheath can be very longand flexible to allow delivery from an insertion point distant from theheart as is understood by the skilled artisan.

FIG. 25D shows that the distal end of the implantation device has beenadvanced through the mitral valve such that at least a portion of thefirst sheath which encases the valve prosthesis support frame is locatedwithin the left ventricle. In an alternative embodiment, theimplantation device may be advanced distally until the valve prosthesiswithin the first sheath is positioned within the native valve.

FIG. 25E shows that second sheath 130 has been pushed distally whilevalve claspers, e.g., valve clasper 106, is held stationary, to uncoverthe valve claspers, allowing the u-shaped members of the valve claspersto expand radially from the central axis of the delivery device.

FIG. 25F shows that the first sheath with encased valve prosthesissupport frame 102 in its compact condition is pulled proximally withvalve claspers, e.g., valve clasper 106, until the u-shaped members ofthe valve claspers contact or otherwise engage the native valve. Theuser does not need to rely on imaging for this manipulation as the useris able to feel resistance when the u-shaped members of the valveclaspers contact the native valve.

FIG. 25G shows that first sheath 122 has been advanced in a distaldirection until the distal edge of first sheath 122 abuts or contact theapex of the valve claspers.

FIG. 25H shows the implantation device after first sheath 122 has beenpulled in a proximal direction to uncover valve prosthesis support frame102 allowing the support frame to expand or deploy to its expandedcondition. At this time, the native valve leaflets are positionedbetween the valve claspers and the support frame. More specifically, thevalve leg member of the valve clasper is positioned between the nativevalve leaflet and the support frame, and the native valve leaflet ispositioned between the valve clasper leg member and the valve clasperu-shaped member. FIG. 25H also shows track wire 150 still reversiblyattached to valve clasper 106 and pusher wire 170 still engaged withsupport frame 102.

FIG. 25I shows that the track wires have been pulled in a proximaldirection to unattach them from the valve claspers. Pusher wires 170 arestill engaged with the valve prosthesis support frame, helped tomaintain the valve prosthesis in its desired position as the track wiresare unattached.

FIG. 25J shows that the pusher wires have been pulled in a proximaldirection to disengage each pusher wire from the valve prosthesissupport frame.

FIG. 25K shows that first sheath 122 has been pushed in a distaldirection until it abuts the proximal edge of second sheath 130.

FIG. 25L shows proximal movement of the implantation device to removethe device from the patient while leaving the valve prosthesis in thenative heart valve.

X. Method for Deploying a Valve Prosthesis Via Superior Vena CavaDelivery

In an eighth aspect, a method for delivering the valve prosthesisdescribed herein in a compressed form or compact condition to the heartusing an implantation device 100 via percutaneous delivery through thesuperior vena cava is provided and is shown in FIG. 27. In this aspect,the valve prosthesis is a pulmonary valve prosthesis.

Implantation device 100 for delivery of a pulmonary valve prosthesisthrough the superior vena cava is inserted into the superior vena cavaof the patient. Prior to inserting the implantation device into theheart, a guidewire 110 is introduced into the jugular vein and thenadvanced using an imaging through the superior vena cava into the rightatrium, then through the tricuspid valve into the right ventricle andthrough the native pulmonary valve annulus into the pulmonary artery.

In one embodiment, an introducer is first inserted into the jugular veinalong guidewire 110 and implantation device 100 is inserted through theintroducer. In one embodiment, implantation device 100 as describedabove may be inserted into the jugular vein and advanced through thesuperior vena cava into the right atrium. The distal end of theimplantation device is then advanced through the tricuspid valve intothe right ventricle, then through the native pulmonary valve and intothe pulmonary artery as shown in FIG. 28.

After introduction of the implantation device into the right ventricle,the device is advanced along the guidewire until the valve claspers arelocated past the native pulmonary valve. First sheath 120 encasingprosthetic valve support frame 102 in a compact condition is alsoadvanced to a position approximately adjacent and proximal to (below)the native pulmonary valve. It can be appreciated that the once secondsheath 130 encasing the valve claspers is located past the nativepulmonary valve and in the pulmonary artery, methods for positioning anddeploying the prosthetic pulmonary valve are the same or very similar tothose described above for implanting a mitral prosthetic valve usingimplantation device 100.

XI. Method for Deploying a Valve Prosthesis Via Femoral Artery Delivery

In a ninth aspect, a method for delivering the valve prosthesisdescribed herein in a compressed form or compact condition to the heartusing implantation device 300 is provided. In one embodiment, the valveprosthesis is an aortic valve prosthesis delivered via the femoralartery.

A guidewire is inserted into the femoral artery according to methodsknown in the art and advanced through the femoral artery, the aorticarch, and the aortic valve as shown in FIG. 29A.

FIG. 29B shows implantation device 300 after it has been inserted intothe femoral artery and guided through the aortic arch, then advancedalong the guidewire until the distal end of the second sheath positionedabove the native aortic valve 302. One would readily understand that inthis embodiment, the first sheath has a length sufficient to extend fromthe location at which the implantation device enters the patient pastthe aortic valve. The first sheath is also made of a material flexibleenough and with a diameter small enough to be advanced safely throughthe femoral artery.

FIG. 29C shows implantation device 300 after the valve claspers, such asvalve claspers 324 a, 324 b, have expanded radially from the centralaxis of the implantation device. In this embodiment, the implantationdevice comprises three valve claspers, each with a u-shaped memberhaving a curved portion and a straight portion as described above. Thecurved portion of each valve clasper 324 may be uncovered by movingsecond sheath 310 distal while holding the valve claspers stationary, ormoving track wires 344 in a proximal direction. Prior to insertion ofthe implantation device into the patient, the curved portion of thevalve claspers are only slightly covered by the proximal end of thesecond sheath. After the curved portion of valve clasper 324 isuncovered, track wires 344 are moved in a proximal direction to uncoverthe entirety of each of the valve claspers. At this time, shown in FIG.29C, the straight portions of each valve clasper are encased at leastpartially in the track wires such that each track wire encases onestraight portion of two separate valve claspers. In this embodiment, theimplantation device comprises three track wires. Additionally, as shownin FIG. 13B, each track wire can encase a locking wire. As shown inFIGS. 14A-14D, the delivery device in one embodiment may comprise atrack wire support 356 which may encase the plurality of track wires.FIG. 29C shows the valve claspers in an engagement position.

FIG. 29D shows that the track wires are advanced distally until thecurved portion of each valve clasper engages the floor of the aorticsinus. Here, the valve claspers are in the nested position. Thismovement may be accomplished by pushing track wire controller 342 in adistal direction.

FIG. 29E shows that second sheath 310 is pushed in a distal direction tomove second sheath 310 in a distal direction to at least partiallyuncover prosthetic valve 305. This movement may be accomplished bysecond sheath controller 338 in a distal direction. At this time,prosthetic valve support frame 305 partially expands or deploys. Asprosthetic valve support frame 305 partially deploys, the straightportions of the valve claspers are still encased by a track wire.Expanding only a portion of the support frame (as indicated in FIGS.1C-1D) may help to prevent the support frame from “jumping” out ofposition upon partial or full deployment of the support frame.Alternatively, the entire support frame may be uncovered and expanded ina single step. In some embodiments, the straight portions of the valveclaspers have been threaded through a covering on the external face ofthe valve prosthesis support frame such that a minimal portion of thevalve clasper is positioned between the covering and the valve supportframe.

FIG. 29F shows that second sheath 310 has been moved in a distaldirection to advance second sheath 310 in a distal direction to fullyuncover and deploy valve prosthesis support frame 305. This movement ofthe second sheath may be achieved by distally moving second sheathcontroller 336. Upon full deployment of valve prosthesis support frame305, straight portions of valve claspers 324 are still encased by trackwires 344.

Track wires can be detached from the valve claspers by moving at leastone release switch, such as release switch 320 a or 320 b in a proximaldirection while holding the delivery device stationary so that at leastone locking wire 328 is held stationary. In doing so, friction betweenlocking member 329, the straight portions of two valve claspers 324, andtrack wire 344 is removed and at least one track wire and a locking wiremay be moved in a proximal direction without applying any pulling forceon valve clasper 324 such that the valve claspers 324 are released fromthe track wires. The delivery device after release of the valve claspersfrom the track wires is shown in FIG. 29G. In one embodiment,illustrated in FIG. 29G, the track wires are moved in a proximaldirection by pulling track wire controller 342 in a proximal direction.

FIG. 29H shows that second sheath controller 336 can be pulled in aproximal direction to position second sheath 310 adjacent to firstsheath 308. Delivery device 300 is then removed from the patient whileleaving the valve prosthesis deployed within the native aortic valve.

XII. An Alternative Method for Deploying a Valve Prosthesis Via FemoralArtery Delivery

In a tenth aspect, a method for delivering the valve prosthesisdescribed herein to the aortic valve using implantation device 400 viathe femoral artery is provided. Implantation device 400 can be used todeliver a variety of valve prostheses included those described hereinwith valve claspers 425 in which the valve claspers are movable alongthe longitudinal axis of the valve prosthesis or in which the valveclaspers are fixed on support frame 470 of the valve prosthesis.

An embodiment of a method for deploying implantation device 400 by wayof the femoral artery is illustrated in FIGS. 15A-15C. In thisembodiment, a guidewire 110 is inserted into a femoral artery of asubject and advanced along the guidewire past the malfunctioned aorticheart valve into the left ventricle of the heart under the guidance ofan imaging system using methods known to those having ordinary skill inthe art. Implantation device 400 is then inserted into the femoralartery along the guidewire such that first sheath 420 which encasessupport frame 440 of a valve prosthesis is pushed into the target sitein the vicinity of the malfunctioned native heart valve by following thepath of the guidewire such that second sheath 430 which encases valveclaspers 425 is above the native heart valve. This placement of theimplantation device is guided by an imaging system and by moving theimplantation device along the guidewire. It will be appreciated by aperson having ordinary skill in the art that the implantation device isin the vicinity of the malfunctioned native heart valve when theposition of the implantation device is such that upon removal of thefirst sheath, the valve prosthesis will deploy in a position that willallow the valve prosthesis to perform its intended function.

In one embodiment, implantation device 400 further comprises a controlunit 410. The control unit comprises a first sheath switch 445 and asecond sheath switch 435. The first sheath switch is attached by a wireor comparable member to the first sheath. The second sheath switch isattached by a wire or comparable member to the second sheath. Onceimplantation device 400 is in the vicinity of the target site, thesecond sheath switch is moved or adjusted such that the second sheath ismoved in a proximal direction (toward the control unit) to uncover thevalve claspers, as illustrated in FIGS. 15A-15B. This action allows thevalve claspers to extend radially from the leg members.

In one embodiment, the implantation device further comprises a clasperpusher 460 located within and/or movably attached to the second sheath.When the second sheath switch is, for example, moved from the initialposition distal position to a proximal position, this action moves theclasper pusher to the distal end of the second sheath. The clasperpusher engages the proximal end of the valve claspers such that when thesecond sheath switch is moved from the proximal position to the distalposition (see FIGS. 15B-15C), the clasper pusher engages the proximalend of the valve claspers to push the valve claspers in a distaldirection. In one embodiment, the valve claspers are pushed down(distal) by the clasper pusher to a position approximately adjacent tothe native heart valve sinus. In one embodiment, the valve claspers arepushed down a predefined distance.

In one embodiment, implantation device 400 further comprises a valvestopper 450 located within and/or attached to first sheath 420. Thevalve stopper functions to hold the prosthetic valve in place as thevalve claspers are pushed in a distal direction.

After the valve claspers are positioned in the native heart sinus, firstsheath 420 is pushed down (in a distal direction, further into the leftventricle) to release support frame 440 of the valve prosthesis from thefirst sheath by switching first sheath switch 445 from its initialproximal position (FIG. 15B) to its distal position (FIG. 15C).Unsheathed valve support frame 470 radially expands, causing the valveclaspers to clasp onto the native heart valve leaflets 490 as shown inFIG. 15C.

After ensuring the valve prosthesis is properly placed, the first sheathis pulled in a proximal direction to abut the second sheath. In oneembodiment, this motion is accomplished by switching first sheath switch445 back from its distal position to its proximal position. This is doneto prepare the implantation device for retrieval. The implantationdevice is then gently pulled out in a proximal direction from thesubject along the guidewire, which is next retrieve. The deployed heartprosthesis is held in place by the radial expansion force of valvesupport frame 440 and by the plurality of valve claspers 425 claspingonto the native heart valve leaflets.

XIII. An Alternative Deployment Method

FIGS. 30A-30C depict an alternative method of releasing a valveprosthesis support frame 715 from a sheath when positioning the supportframe within a native valve. As shown in FIG. 30A, valve claspers 700are released from sheath 705. In one embodiment, the valve claspers arepushed distally from sheath 705 by pushing release buttons 720 a, 720 bin a distal direction.

FIG. 30B shows that only the distal portion of valve prosthesis supportframe 715 has been pushed distally out of sheath 705 and only thisportion has expanded. Pushing support frame 715 distally out of sheath705 may be accomplished by pushing pusher wire controller 710 distallywhile holding sheath 705 stationary. This method may be accomplishedusing a valve prosthesis support frame as illustrated in FIGS. 1C-1D.

Sheath 705 is then pushed distally to push partially expanded supportframe 715 distally to abut the apex of valve claspers 700, as shown inFIG. 30C. Note that pusher wire controller 710 can be moved at the sametime.

Also noted with this embodiment, when claspers 700 are exposed, trackwires which are still attached to leg members extend at an outward anglefrom sheath 705 as shown in FIG. 30A. Pusher wire controller 710 canthen be moved in a proximal direction to uncover the distal portion ofvalve prosthesis support frame 715, as shown in FIG. 30B. The distalportion of support frame 715 then radially expands while the proximalportion of valve prosthesis support frame 715, remains in a compactcondition within sheath 705. Pusher wire controller 710 and the firstsheath are then moved in a distal direction until the distal end of thevalve prosthesis abuts the clasper apex. Sheath 705 is then moved in aproximal direction to fully expose and deploy the valve prosthesis.

XIV. Delivery Device

In an eleventh aspect, a device for delivery of a medical prosthesisinto a patient is provided. In one embodiment, the device for deliveryof a medical prosthesis into a patient comprises a tubular steering wireextending from a distal end of the device to a proximal end of thedevice, a control unit at the proximal end of the device, a first sheathcomprising an open lumen and positioned distally with respect to thecontrol unit, and at least one track wire. The at least one track wiremay be a solid or hollow wire or cable.

In one embodiment, the device for delivery further comprises a trackwire controller. The track wire may be fixed to the track wirecontroller at its proximal end. In another embodiment, the track wirecontroller is fixed at its proximal end to a switch, dial or othermovable control or member. The movable control or member may allow anoperator to control the movement and/or position of the track wireindependently of the device.

In one embodiment, the device further comprises a pusher wire having aproximal end fixed to the control unit and a distal end which may engagethe medical prosthesis.

In one embodiment, the device further comprises a second sheath. Inanother embodiment, the second sheath is positioned serially with thefirst sheath. In one embodiment, the second sheath is positionedproximal to the first sheath. In another embodiment, the second sheathis positioned distal to the first sheath. In yet another embodiment, thesecond sheath is positioned concentric with the first sheath.

In one embodiment, the control unit of the device for delivery furthercomprises a second sheath controller. In one embodiment, the secondsheath controller comprises a central control cable (second sheathcontrol cable) that extends from the second sheath to the second sheathcontroller. The second sheath controller may allow the operator to movethe second sheath independently of the other device components.

In one embodiment, the second sheath controller comprises the tubularsteering wire secured at its distal end to the second sheath and affixedat its proximal end to the second sheath controller.

In one embodiment, the control unit of the delivery device furthercomprises a first sheath controller.

While a number of exemplary aspects and embodiments have been discussedabove, those of skill in the art will recognize certain modifications,permutations, additions and sub-combinations thereof. It is thereforeintended that the following appended claims and claims hereafterintroduced are interpreted to include all such modifications,permutations, additions and sub-combinations as are within their truespirit and scope.

The invention claimed is:
 1. An implantation device, comprising a valveprosthesis comprising a support frame radially expandable between acompact condition and an expanded condition, the support frame having anouter surface and a longitudinal axis along an inflow-outflow directionand defining a central orifice about the longitudinal axis and at leastone valve clasper movably attached to the support frame such that duringvalve delivery the at least one valve clasper is movable relative to thesupport frame along the longitudinal axis and between a nesting positionwith the outer surface of the support frame and an engagement positionwith a native cardiac valve sinus wherein the at least one valve clasperis physically separated from the support frame, and a delivery devicecomprising a control unit; and at least one track wire, the at least onetrack wire having a proximal end attached to the control unit and adistal end for contact with the at least one valve clasper.
 2. Theimplantation device of claim 1, further comprising a first sheath whichat least partially encases the support frame.
 3. The implantation deviceof claim 2, further comprising a second sheath which at least partiallyencases the at least one valve clasper.
 4. The implantation device ofclaim 3, wherein the first sheath is positioned serially and distally tothe second sheath.
 5. The implantation device of claim 3, wherein thesecond sheath is positioned serially and distally to the first sheath.6. The implantation device of claim 2, wherein prior to delivery of thevalve prosthesis, the support frame is fully encased by the firstsheath.
 7. The implantation device of claim 1, wherein the at least onetrack wire is reversibly attached to the at least one valve clasper. 8.The implantation device of claim 1, wherein the at least one valveclasper comprises three u-shaped members.
 9. The implantation device ofclaim 1, wherein the at least one valve clasper is a multiplex unitcomprising two or more u-shaped members and two or more apex members,wherein a first u-shaped member is permanently attached to a secondu-shaped member via a first apex member and a second apex member. 10.The implantation device of claim 1, wherein the at least one valveclasper is a multiplex unit comprising three u-shaped members and threeapex members, wherein each of the three u-shaped members is permanentlyattached to another of the three u-shaped members via one of the threeapex members.
 11. The implantation device according to claim 1, whereinthe at least one valve clasper is comprised of a shape memory metal. 12.The implantation device of claim 1, wherein the support frame iscomprised of a shape memory metal.
 13. The implantation device of claim1, wherein a plurality of leaflets is attached to the support frame,wherein the plurality of leaflets provides a one-way valve in thecentral orifice when the support frame is in its expanded condition. 14.The implantation device of claim 1, wherein the valve prosthesiscomprises three valve claspers coupled to each other at respective apexmembers thereof, wherein the valve prosthesis further comprises threeleg members coupled to and extending longitudinally from the apexmembers between adjacent valve claspers.
 15. The implantation device ofclaim 14, wherein the three leg members each comprise barbs extendingtherefrom.
 16. The implantation device of claim 1, wherein the valveprosthesis comprises three valve claspers, wherein each valve claspercomprises a u-shaped member and opposing apex members extending from theu-shaped member, wherein each apex member is curved.
 17. Theimplantation device of claim 16, wherein adjacent valve claspers arejoined together via the apex members, each apex member having a vertex,and wherein adjacent apex members intersect to form a valley between thevertices of the adjacent apex members.
 18. The implantation device ofclaim 17, further comprising a hole formed between the adjacent apexmembers.
 19. The implantation device of claim 1, wherein the valveprosthesis comprises three valve claspers that are joined together inseries at respective apex joints, each apex joint having two verticesand a valley interposed between the two vertices.
 20. The implantationdevice of claim 19, wherein each apex joint comprises a hole formedtherein.